forgot to address this:

It sounds like you're committing the Pascal's Wager Fallacy Fallacy. If you aren't, then I'm not understanding your point. Large future utilities should count more than small future utilities, and multiplying by low probabilities is fine if the probabilities aren't vanishingly low.

If the probabilities aren't vanishingly low, you reach basically same conclusions without requiring extremely large utilities. 7 billion people dying is quite a lot, too. If you see extremely large utilities on a list of requirements for caring about the issue, when you already have at least 7 billion lives at stake, then it is a Pascal's wager.

Actually, I don't see vanishingly small probabilities problematic, I see small probabilities where the bulk of probability mass is unaccounted for, problematic. E.g. response to low risk from a specific asteroid is fine, because it's alternative positions in space are accounted for (and you have assurance you won't put it on an even worse trajectory)