Lots to digest here.

I'm going to bring the Dunning-Kruper Effect into the picture. I've had too many people in my life who thought they were very smart but actually weren't. Their psyche is not set up to learn new things because they already have all the answers.

I don't think it's a case of "exaggerate the intellectuality of mankind" but more to understand its current condition and work with that. That means wisely deal with so much DKE around.