Or, imagine if in 2014, Yudkowsky suddenly started saying the Copenhagen interpretation of quantum mechanics is correct, without acknowledging that anything had changed. That’s how weird this is.
This is a strong overstatement. Eliezer clearly has invested orders of magnitude more effort in defense of his MWI stance than he did in defense of his original dolphins-aren’t-fish “stance”.
Kudos on taking the time to tighten and restate your argument! I’d like to encourage more of this from alignment researchers, it seems likely to save lots of time taking past each other and getting mired on disagreements over non-cruxy points.