I don't think longtermism necessarily needs new priorities to be valuable if it offers a better perspective on existing ones (although I don't think it does this well either). 

Understanding what the far future might need is very difficult. If you'd asked someone 1000 years what they should focus on to benefit us, you'd get answers largely irrelevant to our needs today.^[1] If you asked someone a little over 100 years ago their ideas might seem more intelligible and one guy was even perceptive enough to imagine nuclear weapons, although his optimism about what became known as mutually assured destruction setting the world free looks very wrong now, and people 100 years ago that did boring things focused on the current world did more for us than people dreaming of post-work utopias. 

To that extent, the focus on x-risk seems quite reasonable: still existing is something we actually can reasonably believe will be valued by humans in a million years time^[2] Of course, there are also over 8 billion reasons to try to avoid human extinction alive today (and most non-longtermists consider at least as far as their children) but longtermism makes arguments for it being more important than we think. This logically leads to willingness to allocate more money to x-risk causes, and consider more unconventional and highly unlikely approaches x-risk. This is a consideration, but in practice I'm not sure that it leads to better outcomes: some of the approaches to x-risk seeking funding make directionally different assumptions about whether more or less AGI is crucial to survival: they can't both be right and the 'very long shot' proposals that only start to make sense if we introduce fantastically large numbers of humans to the benefit side of the equation look suspiciously like Pascal's muggings.^[3] 

Plus people making longtermist arguments typically seem to attach fairly high probabilities to stuff like AGI that they're working on in their own estimations, which if true would make their work entirely justifiable even focusing only on humans living today.

(A moot point but I'd have also thought that although the word 'longtermist' wasn't coined until much later, Bostrom and to a lesser extent Parfit fit in with the description of longtermist philosophy. Of course they also weren't the first people to write about x-risk)

1. ^{^}

   I suspect the main answers would be to do with religious prophecies or strengthening their no-longer-extant empire/state

2. ^{^}

   Notwithstanding fringe possibilities like the possibility humans in a million years might be better off not existing, or for impartial total utilitarians humanity might be displacing something capable of experiencing much higher aggregate welfare.

3. ^{^}

   Not just superficially in that someone is asking to suspend scepticism by invoking huge reward, but also that the huge rewards themselves make sense only if you believe in very specific claims about x-risk over the long term future being highly concentrated in the present (very large numbers of future humans in expectation or x-risk being nontrivial for any extended period of time might seem superficially uncontroversial possibilities but they're actually strongly in conflict with each other). 

Why on earth would you set 2017 as a cutoff? Language changes, there is nothing wrong with a word being coined for a concept, and then applied to uses of the concept that predate the word. That is usually how it goes. So I think your exclusion of existential risk is just wrong. The various interventions for existential risks, of which there are many, are the answer to your question.

Great question

Based on conversations I've had, I believe the focus in EA on longtermism has been off-putting for a lot of people and has probably cost a lot of support and donations for other EA causes.

Was it all a terrible waste?

I think my basic reaction here is that longtermism is importantly correct about the central goal of EA if there are longtermist interventions that are actionable, promising and genuinely longtermist in the weak sense of "better than any other causes because of long-term effects", even if there are zero examples of LT interventions that meet the "novelty" criteria, or lack some significant near-term benefits. 

Firstly, I'd distinguish here between longtermism as a research program, and longtermism as a position about what causes should be prioritized right now by people doing direct work. At most criticisms about novelty seem relevant to evaluating the research program, and deciding whether to fund more research into longtermism itself. I feel like they should be mostly irrelevant to people actually doing  cause prioritization over direct interventions. 

Why? I don't see why longtermism wouldn't count as an important insight for cause prioritization if it was the case that thinking longtermistly didn't turn up any new intervention that we're not already known to be good, but it did change the rankings of interventions so that I changed my mind about which interventions were best. That seems to be roughly what longtermists themselves think is the situation with regard to longtermism. It's not that there is zero reason to do X-risk reduction type interventions even if LT is false, since they do benefit current people. But the case for those interventions being many times better than other things you can do for current people and animals rests on, or at least is massively strengthened by Parfit-style arguments about how there could be many happy future people. So the practical point of longtermism isn't to produce novel interventions, necessarily, but also to help us prioritize better among the interventions we already knew about. Of course, the idea of Parfit-style arguments being correct in theory is older than using it to prioritize between interventions, but so what? Why does that effect whether or not it is a good idea to use it to prioritize between interventions now? The most relevant question for what EA should fund isn't "is longtermist philosophy post -2017 simultaneously impressively original and of practical import" but "should we prioritize X-risk because of Parfit-style arguments about the number of happy people there could be in the future." If the answer to the latter question is "yes", we've agreed EAs should do what longtermists want in terms of direct work on causes, which is at least as important than how impressed we should or shouldn't be with the longtermists as researchers.* At most the latter is relevant to "should we fund more research into longtermism itself", which is important, but not as central as what first-order interventions we should fund. 
To put the point slightly differently, suppose I think the following: 

1) Based on Bostrom and Parfit-style arguments-and don't forget John Broome's case for making happy people being good-I think it's at least as influential on Will and Toby-the highest value thing to do is some form of X-risk reduction, say biorisk reduction for concreteness.

2) If it weren't for the fact that there could exist vast numbers of happy people in the far future, the benefits on the margin to current and near future people of global development work would be higher than biorisk reduction, and should be funded by EA instead, although biorisk reduction would still have significant near-term benefits, and society as a whole should have more than zero people working on it. 

Well, then I am a longtermist, pretty clearly, and it has made a difference to what I prioritize. If I am correct about 1), then it has made a good difference to what I prioritize, and if I am wrong about it, it might not have done. But it's just completely irrelevant to whether I am right to change cause prioritization based on 1) and 2) how novel 1) was if said in 2018, or what other insights LT produced as a research program.  

None of this is to say 1), or its equivalent about some other purpoted X-risk, is true. But I don't think you've said anything here that should bother someone who thinks it is. 

Quick question - Is AI safety work considered a "long-termist" intervention? I know it has both short term and long term potential benefits, but what do people working on it generally see it as?

I suppose if you are generally pretty doomer, it wouldn't meet your 4th criteria. "Genuinely longtermist: it’s something that we wouldn’t want to do anyway based on neartermist concerns"

Also one would hope that it wouldn't be too long before @Forethought has cranked out one or too, as I think finding these is a big part of why they exist...

Something can be a promising X intervention even if its something that had been thought of before in connection with another purpose.

For example, GLP-1 blockers are promising obesity interventions. When we discovered they were very effective at weight loss, this was an important intellectual contribution to the world. It gave fat people a new reason to take the drugs. This is true even though GPL-1s were already an approved medical intervention for a different purpose (diabetes).

Even beyond this, I think Nick's Astronomical Waste argument is Longtermist. So in that sense it is a novel Longtermist idea, even if it predates the term 'Longtermism'.

My biggest takeaway from the comments so far is that many/most of the commenters don't care whether longtermism is a novel idea, or at least care about that much less than I do. I never really thought about that before — I never really thought that would be the response.

I guess it's fine to not care about that. The novelty (or lack thereof) of longtermism matters to me because it sure seems like a lot of people in EA have been talking and acting like it's a novel idea. I care about "truth in advertising" even as I also care about whether something is a good idea or not.

I think the existential risk/global catastrophic risk work that longtermism-under-the-name-"longtermism" builds on is overall good and important, and most likely quite actionable (e.g. detect those asteroids, NASA!), even though there may be major errors in it, as well as other flaws and problems, such as a lot of weird and farfetched stuff in Nick Bostrom's work in particular. (I think the idea in Bostrom's original 2002 paper that the universe is a simulation that might get shut down is roughly on par with supernatural ideas about the apocalypse like the Rapture or Ragnarök. I think it's strange to find it in what's trying to be serious scholarship, and it makes that scholarship less serious.)

The fundamental point about risk is quite simple and intuitive: 1) humans are biased toward ignoring low-probability events that could have huge consequences and 2) when thinking about such events, including those that could end the world, we should think not just about the people alive today, the world today, but the consequences for the world for the rest of time and all future generations. 

That's a nearly perfect argument! It's also something you can explain in under a minute to anyone, and they'll intuitively get it, and probably agree or at least be sympathetic. 

As I recall, when NASA did a survey of or public consultation with the American public, the public's desire for NASA to work on asteroid defense was overwhelmingly higher than NASA expected. I think this is good evidence that the general public finds arguments of this form persuasive and intuitive. And I believe when NASA learned that the public cared so much, that led NASA to prioritize asteroid defense much more than it had been previously.

I don't have any data on this right now (I could look it up), but to the extent that people — especially outside the U.S. — haven't turned covid-19 into a politically polarized, partisan issue and haven't bought into conspiracy theories or pseudoscience/non-credible science, I imagine that, among people who thought the virus was real, the threat was real, and the alarmed response was appropriate, there would be strong support for pandemic preparedness. This isn't rocket science — or, with asteroid defense, it literally is, but understanding why we want to launch the rockets isn't rocket science.

I agree that trying to make moral progress has near-term benefits but, particularly in some areas like animal welfare, progress can feel dishearteningly slow. The accumulated benefit from 1000 years of tiny steps forward in terms of moral progress could be pretty huge, but perhaps it won't ever feel massively significant within any one person's lifetime. That makes it feel longtermist, though I accept that it feels quite vague to be considered an actionable longtermist intervention.