Ok, I have a real crackpot physics theory now.

What if the many-worlds interpretation of QM is correct, but that the many worlds don’t require any physical existence because determinism is true, but unverifiably so? Meaning that the many worlds exist sort of like virtual particles that never instantiate because determinism means that only one world can actually exist.

Ok, now that’s a crackpot physics theory I can find no evidence anywhere of anyone cracking enough to produce such a pot!