The same issue applied to live-to-1000. If there is a global catastrophe anywhere in the next 1000 years, then living-to-1000 doesn't happen, so it's a heavy discount factor. If there is a FAI, it's also unclear whether original individuals remain and it makes sense to count their individual lifespans.

Good point, and I think it explains one of the funny results that I found in the data. There was a relationship between strength of membership in the LW community and the answers to a lot of the questions, but the anti-agathics question was the one case where there was a clear non-monotonic relationship. People with a moderate strength of membership (nonzero but small karma, read 25-50% of the sequences, or been in the LW community for 1-2 years) were the most likely to think that at least one currently living person will reach an age of 1,000 years; those with a stronger or weaker tie to LW gave lower estimates.

There was some suggestion of a similar pattern on the cryonics question, but it was only there for the sequence reading measure of strength of membership and not for the other two.