Nobody disagrees with this. But since you brought it up, I think it's worth asking: what precisely has the EA movement done to reduce, even marginally, the risk of a nuclear war?
Nothing that I'm aware of. In general I think that most of the current "longtermist" organizations are useless - but that doesn't mean they're incorrect.
I don’t belong to the EA movement, so maybe it just isn’t my place to say what should or shouldn’t be EA. But this kind of bootstrapping of classroom ethical dilemmas into actually diverting donated money away from human welfare efforts astounds me.
I agree that they're ineffective, but I don't see any evidence that the MIRI types are lying - they're trying to help, they think they're helping ... and they're mostly wrong. It happens.
> But this kind of bootstrapping of classroom ethical dilemmas into actually diverting donated money away from human welfare efforts astounds me.
Are you sure that's what's actually going on? Donations and especially effort are not fungible. The techy libertarian futurist types in the MIRI orbit, for instance, are so far as I can tell simply not as bothered by poverty as Singer et al. A world in which they're not worried about AI risk is not a world in which they give just as much to other causes; it's a world in which they give less.
https://www.givingwhatwecan.org/cause-areas/long-term-future...
https://80000hours.org/problem-profiles/nuclear-security/
https://www.effectivealtruism.org/articles/carl-robichaud-fa...
It sounds ridiculous to you because you framed it in an uncharitable way. Another way of saying "maximize the likelihood of a galaxy filled with colonized planets", so far as contemporary people are concerned, is "minimize the likelihood of civilizational collapse". Even a marginal reduction in the risk of nuclear war, for instance, would be a very good thing.