Attempting to understand the reasons for the widespread acceptance of Plato and of religion is an illuminating but exceptionally frustrating exercise to come to grips with how humanity wasted so much potential.
Seems to have frustrated Jefferson too, especially in his question as to why Cicero would have accepted it. I don't have any ultimate answers but I do think this question is near the root of everything, and the best vehicle for getting to the bottom of that root, and "rooting it out" is through Epicurus. He's our primary connection to a chain of 2000 years of fighting back against this problem.