I hope this ruffles some feathers. As you say, it’s hard to carry the point home, but I definitely think there is something there.
One nit-pick, Freud doesn’t conclusively prove the metaphysical point because he’s not so interested in it. True, he’s an atheist and he assumes he’s writing for like-minded peers, so that assumption prevails, but what really interests him in the question of religious belief is something like “how is it possible for these various stances towards the absolute to be so immediately intuitive to the human being?” Then he points out that it’s based on a model that every human being has by necessity (sharing the same experiences of infancy and most of early childhood), as well as features of his posited meta-psychology, as you’ve discussed. So religious belief “locks” into a pattern carved out by family life, which allows it to becomes deeply saturated in affective dimensions, not just intellectual. That’s the epistemological question you mention, but also it crosses over into ethical categories once its set up like that.
So, in the tiresome debate by bible thumping fundamentalists and neo-anglophone atheists, the intellectual dimension is ridiculous, both sides are guilty of all kinds of category mistakes and logical fallacies and so on, but the interesting question is, then, what makes this debate so intense despite metaphysical questions not being ordinarily suited to get people red in the face? Both sides will point to rational/intellectual reasons for why the debate rubs them so violently, but from the Freudian perspective these are all ad hoc, and the real phenomenon is always evinced by what it is that gets people jumping up and down and shouting, that always points to a deep and tumultuous well of affect, indicating that the beliefs involved are covertly taking part in more primal structures. So, the infuriatingly annoying Freudian question is “Yes, yes, yes, that’s all very true, by why do you care so much? Why are you taking it in this way?”
