A motivating scenario could be: imagine you are trying to provide examples to help convince a skeptical friend that it is in fact possible to positively change the long-run future by actively seeking and pursuing opportunities to reduce existential risk.
Examples of things that are kind of close but miss the mark
- There are probably decent historical examples where people reduced existential risk but where thoes people didn't really have longtermist-EA-type motivations (maybe more "generally wanting to do good" plus "in the right place at the right time")
- There are probably meta-level things that longtermist EA community members can take credit for (e.g. "get lots of people to think seriously about reducing x risk"), but these aren't very object-level or concrete
I think my motivation comes from things to do with: helping with my personal motivation for work on existential risk, helping me form accurate beliefs on the general tractability of work on existential risk, and helping me advocate to other people about the importance of work on existential risk.
Thinking about it maybe it would be pretty great to have someone assemble and maintain a good public list of answers to this question! (or maybe someone did already and I don't know about it)