Both skip the return of the enlightened (probably for pacing purposes and because from a storytelling perspective it’s kinda cliche to have a “no one believes me” scene these days), but they still agree with Plato’s stance that the unenlightened aren’t worth bothering with.
Neither Agent Jay nor Harry tries to explain the aliens/wizarding world to the outsiders because A) they’re told not to and B) they wouldn’t believe/wouldn’t be able to deal with it, just like we said.
They pretty much do the math on the return of the enlightened off-screen. All introducing the aliens/wizards to the populace would really do is cause more problems by making them feel insecure, like any minority group does to the majority on a day-to-day basis (observe the gay rights movement of the last few decades), which in turn simply makes the big, stupid majority want to stomp them out.
Any kind of fantasy story that deals with a world on top of the “real world” goes through the exact same motions anyway. It may not follow Plato’s scenario blow-by-blow, but the intent is still there.