I think the reality is that Eliezer Yudowsky, while a very bright mind and great man in terms of rationality, has overstepped his limits when it comes to physics.

He do admit that there is currently no satisfactory solution to the Born Rule issue, yet he has written several posts talking about MWI as it is "obviously true". That is quite irrational. Quantum mechanics is, after all, ALL about the probabilities predicted by Born Rule, that is the essence of QM, if a model gets these probabilities wrong, it is obviously in deep trouble.

I am quite dissapointed in Yudowsky for not admitting that he may have overstepped his area of expertise and mislead people to think that the case for MWI was stronger than it ACTUALLY is.

I think it might be that he thinks the only other alternative is anti-realism or indeterminism, which is wrong, I dispise and absolutely object to both antirealism and indeterminism, but thee are other realist interpretations out there and the fact that we got no quantum gravity solution nor any ToE should force even the most stubborn MWI'ers to keep their minds open and refrain from claiming that it is true.