I think it would be more helpful if you directly learned that most other people live much richer inner lives than you give credit for.

It usually turns out to be less, because I tend to become overly excited about people. Anyway, you can't know what I give them credit for, I'm only talking about one part of their inner lives.

And frankly, MOST of the human race falls into some of your categories at points, especially the ‘ignorant of details’.

All of it, it's a relative thing. For, like I said, a medical professional I am an example of <word I'm looking for> often.

It’s better for your mental health not to stereotype too much or you’ll end up a misanthrope like me.

That's true, but not always avoidable. We need sometimes to put our brain into a certain state to solve tasks. And we can't switch it back for everything else immediately.

Alternatively: you could use the phrase ‘Knowlessman’, as it was a legit derogatory label back in the day, and is pretty clear about its meaning right on the face.

It doesn't quite grasp the part about deceiving oneself that some profession is much simpler than it really is, or some area of life, and so on, and reinforcing that with some tribal feeling. But OK.