The quantum interpretation debate is merely the illustrative starting point for this article, so perhaps it is boorish of me to focus on it. But...

the obvious absurdity of attempts to make quantum mechanics yield a single world.

Even if some form of many worlds is correct, this is going too far.

Eliezer, so far as I can see, in your life you have gone from a belief in objective-collapse theories, derived from Penrose, to a belief in many worlds, derived perhaps from your extropian peers; and you always pose the theoretical choice as a choice between "collapse" and "no-collapse". You do not seem to have ever seriously considered - for example - whether the wavefunction is not real at all, but simply a construct like a probability distribution.

There are at least two ways of attempting "to make quantum mechanics yield a single world" which are obviously not absurd: zigzag interpretations and quantum causal histories. Since these hyperbolic assertions of yours about the superiority and obviousness of many-worlds frequently show up in your discourses on rationality, you really need at some point to reexamine your thinking on this issue. Perhaps you have managed to draw useful lessons for yourself even while getting it wrong, or perhaps there are new lessons to be found in discovering how you got to this point, but you are getting it wrong.