I also cannot resist noting, yet again, that all interpretation of QM that rely on solving the Schrodinger equation have exactly the same complexity, as estimated above, and so cannot be distinguished by the Occam's razor. This applies, in particular, to MWI vs Copenhagen.

Very interesting comment, upvoted. I can't tell that what you are saying makes sense but I welcome and endorse your examination and attempt to reduce the formalization of Occam's razor to practice.