Plus, the state tried and executed Socrates for his troubles. This may have led Plato to distinguish between the brutal material world that runs on illusions and ignorance, and the ideal world, the philosopher's Heaven.

Whether that dualism is metaphysically rather than just politically or theologically justified is another matter. We might wish there were a better world somewhere or that we ought to create one, but that's obviously not the same as saying there's always been this hierarchy in place.