Its setup this way because it makes a very select few unimaginably wealthy and this outsizing their say in the happenings of said society, so it self reinforces.

There is likely a selection biased. A lot of mental health issues and quirks have genetic components. If you have an issue, it's FAR more likely your family has issues.

We also tend to be attracted to like minded individuals. My partner tried to tell me I was normal, until I was diagnosed. They were diagnosed a few years later. It turned out most of their friends were neurodiverse too. They were rating themselves (and me) against a bunch of fellow weirdos!

A lot of the problems have always been there. They were just seen as personal failings and hidden. Now we know that they have an adjustable chemical component that can be used to treat them. That, combined with more people being open about issues has created the spike.

Modernity is not designed for humans and expects humans to evolve to match it and that will take at least hundreds of thousands of years. The sort of society we are currently evolved for only exists in small pockets through out the world.