The difference is the purported evidence for the theory does not hold as all, as opposed to the theory of natural selection which has observable and reproducibl

The difference is the purported evidence for the theory does not hold as all, as opposed to the theory of natural selection which has observable and reproducible evidenced in the form of breeding. You are kind of turning the burden of proof on its head by claiming that the hypothesis could develop into an better theory. You can say than about any unproven hypothesis. Some parts of the theory are unfalsifiable (e.g that ancient people did not have self-awareness) which is impossible to disprove, which means it is not a scientific theory at all. The parts based on "evidence" is easy to disprove: Take the theory that gods speaking to Achilles is the bicameral mind. According to the theory the Odyssey is composed after the watershed moment...but gods are still talking to people. So you need another explanation for that (e.g. it is actually fiction). But in that case you can apply the same explanation to the gods speaking in the Iliad, so the theory does not give you any additional explanatory power.