I’m wrote a book about why all knowledge of the truth is fundamentally uncertain. Give it a read!
I’ve also written a lot about AI safety, personal development, and Buddhism, among other things. Most of that’s here on LessWrong, but there’s also some on my blog, Uncertain Updates.
I think the ontological premises on which this post are based are confused.
In any sense in which we live in multiple worlds, the world of sense experience is first. It’s through our senses, including our internal thought-sense, that we come to know reality and, indeed, construct our experience of it.
Beyond that, all is ontological, including our supposition in the existence of a physical world. This is not to say that the physical world doesn’t exist, but rather that our knowledge of it is mediated by experience, and any extent to which we believe it’s prior to experience is an inference contingent on experience and so not independent and thus makes claims of, e.g., materialism metaphysical claims.
So it seems to me there are only two worlds: the world of raw experience and the world of experience interpreted through ontology. Any other worlds would seem to be sub-worlds of the ontological world, which undermines your argument because they are all made of the same stuff: world models.
Perhaps a better framing would be developmental psychology. In particular, I might offer my own take on ontological development as seeing developmental psychology as a progression of changes in way of relating between reifications (concepts). I think this, or another developmental psychology framework, would provide a better foundation for this line of reasoning, and does suggest a similar conclusion to the one your reach (and one that I happen to agree with!): there’s different kinds of moral worlds accessible to those at later stages of psychological development because their ontology can contain categorically greater complexity.