Dave: Behaving as though objective scientific facts exist has made it possible for me to talk to people all over the world, for the people I care about to be warm in the winter, cool in the summer, have potable water to drink and plenty of food to eat, and routinely survive incidents that would have killed us in pre-scientific cultures, and more generally has alleviated an enormous amount of potential suffering and enabled an enormous amount of value-satisfaction.
I am therefore content to continue behaving as though objective scientific facts exist.
If, hypothetically, it turned out that objective scientific facts didn't exist, but that behaving as though they do nevertheless reliably provided these benefits, I'd continue to endorse behaving as though they do. In that hypothetical scenario you and Alice and Bob and Charlie are free to go on talking about truth-values but I don't see why I should join you. Why should anyone care about truth in that hypothetical scenario?
Similarly, if behaving as though objective moral facts exist has some benefit, then I might be convinced to behave as though objective moral facts exist. But if it's just more talking about truth-values divorced from even theoretical benefits... well, you're free to do that if you wish, but I don't see why I should join you.
Dave: Behaving as though objective scientific facts exist has made it possible for me to ... I am therefore content to continue behaving as though objective scientific facts exist.
I can construct a very similar argument for Christianity (or for most any religion, actually).
Usefulness of beliefs and verity of beliefs are not orthogonal but are not 100% correlated either.
There seems to be a widespread impression that the metaethics sequence was not very successful as an explanation of Eliezer Yudkowsky's views. It even says so on the wiki. And frankly, I'm puzzled by this... hence the "apparently" in this post's title. When I read the metaethics sequence, it seemed to make perfect sense to me. I can think of a couple things that may have made me different from the average OB/LW reader in this regard: