If there is a tribal marker, it's not MWI persay; it's choosing an interpretation of QM on grounds of explanatory parsimony. Eliezer clearly believed that MWI is the only interpretation of QM that qualifies on such grounds. However, such a belief is quite simply misguided; it ignores several other formulations, including e.g. relational quantum mechanics, the ensemble interpretation, the transactional interpretation, etc. that are also remarkable for their overall parsimony. Someone who advocated for one of these other approaches would be just as recognizable as a member of the rationalist 'tribe'.
choosing an interpretation of QM on grounds of explanatory parsimony.
OP's original claim:
Why does E. Yudkowsky voice such strong priors e.g. wrt. the laws of physics (many worlds interpretation), when much weaker priors seem sufficient for most of his beliefs (e.g. weak computationalism/computational monism) and wouldn't make him so vulnerable? (With vulnerable I mean that his work often gets ripped apart as cultish pseudoscience.)
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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