DY: That is a nice Chilluk to make and it’s true for the vast majority of people (though I have heard otherwise normal and knowledgeable people throw the words “Srugi” or “Black Hatter” around as intended insults).
Again, those insults are based on what’s perceived to be inside, not really on the headgear (as you agree).
It’s idiotic to judge a person based on externals like what type of Kippah is worn.
That depends for what. There’s no question that at times we all prejudge. Sometimes it’s useful, and, probably more often,
harmful.