Scenario: You're working hard on an important seeming problem. Maybe you have an idea to cure a specific form of cancer using mRNA. You've been working on the idea for a year or two, and seem to be making slow progress; it is not yet clear whether you will succeed.
Then, you read a blog post or a paper about a similar approach by someone else: "Why I Am Not Working On Cures to Cancer Anymore." They failed in their approach and are giving up. You read their postmortem, and there are a few similarities but most of the details differ from your approach. How much should you update that your path will not succeed?
Maybe a little: After all, they might have tried the thing you're working on too and just didn't mention it. But not that much, since after all they didn't actually appear to try the specific thing you're doing. Even if they had, execution is often more important than ideas anyway, and maybe their failure was execution related.
The same applies for cause prioritization. Someone working on wild animal suffering might read this recent post, and even though they are working on an angle not mentioned, give up. I think in most cases this would be over-updating. Read the post, learn from it, but don't give up just because someone else didn't manage to find an angle.
Last example—climate change. 80000 Hours makes clear that they think it is important but "all else equal, we think it's less pressing than our highest priority areas". (source) This does not mean working on climate change is useless, and if you read the post it becomes clear they just don't see a good angle. If you have an angle on climate change, please work on it!
Indeed, I will go further and make the point: important advances are made by people who have unique angles that others didn't see. To put it another way from the startup world: "the best ideas look initially like bad ideas".
Angles on solving problems are subtle. It's hard to find good ones, and execution matters, so much that even two attempts which superficially have the same thesis could succeed differently.
Don't over-update from others' failures. The best work will be done by people who have unique takes on how to make the world better.