Your definition of what a "nice person" looks like may be predicated on the breadth of your experience with different people. For many (most?) people, the closer someone is to what their friends/family look and act like the "nicer" they are. That's not a condemnation of you or anyone else - it's normal.

I think some humility is in order. It's possible that one is a perfect, unbiased judge of character. On the other hand it's possible that one is just human, with a predilection for equating "like me and my friends" to "nice" or "professional".