Ignorance is bliss.

I often get the impression that so many things are getting from bad to worse worldwide and that the more I know, the more depressed I may get.

If you’re foolish enough to believe in a deity and an after life, perhaps it’s easier to deal with the issues of life. It’s one of the reasons for religion in the first place: keeping people at the bottom of the economy, and those suffering infirmities, content with their status in the expectation that their next one will be better. Those smart enough to not accept the fairytales are forced to deal with life as it is and a constant drive to improve their life. Failure to do that can leave you depressed and feeling hopeless if you are prone to those issues. It is to a certain extent genetic I believe as well.

Yeah I think for me it’s all kinds of things. Partially seeing the world as it is is pretty damn concerning already, plus a bit of extra neurosis thats the downside of thinking a lot in general, plus imposter syndrome and the dunning Krueger effect making us more prone to doubting and underestimating ourselves. To an extent you’ve gotta learn to turn your brain off or at least be a passive observer of it to stay sane at a certain point. Throwing yourself into hard physical tasks also seems to help sooth a worried mind more than most things. Some people don’t realize that “free your mind and your ass will follow” works both ways. Free your ass and your mind will follow.

Sometimes ignorance is bliss.

An article I read in National Geographic in 2014 said that studies of high IQ artistic people showed that the unusually high intelligence was due to a genetic mutation and that set of genes also contained various mental issue "mistakes" as well, especially schizophrenia and manic-depression. So, if those intelligent people intermarry a lot, mental issue genes will express more often and be more serious.

I'd agree with you, they see the world for what it is.