I think people who refuse to entertain the possibility are the deluded ones. Quite misguided, actually. The whole fact of existence and consciousness in any form is still pretty much beyond human explanation, and even without my own subjective experiences of other 'dimensions' I would have to concede the
probability that we live 'other lives'. The mathematics inherent in the structure of the universe establishes that probability. But many 'rationalists' miss that point.
Apart from anything else, when we make even the smallest choice between two or more alternative actions, we leave behind the universe that consists of the opposite action. According to quantum physics, that universe goes on existing somewhere beyond our conscious awareness (and not just as a theory) 😲