I think the Dunning-Krueger effect is also relevant. To some extent, though, average people are better equipped to be experts on everything. We have smart phones and thus the world's knowledge at our fingertips. Previous generations had nothing like that. Naturally, this inflates our egos but it also potentially empowers us.

It's just that that power, as you say, turns out to be illusory. Democratic control is siphoned away even in the US, the "leader of the free world." We're also drowning in so much data that we don't know what's up or down, what's real and what's fake. We end up being controlled by algorithms and addicted to trivialities.

This is a fascinating topic, the nature of the mass man. Nietzsche called them the "last men."