That's great. The point is that you shouldn't disregard the probability of someone seeming "nice" while having issues in private. I don't think that is uncommon.
Also, I don't like how everybody assumes that being "nice" is a good thing. I prefer reasonable and logical people, because when talking to them, I can see that they understand what I am saying, whereas when talking to "nice" people, they have that dreamy aura about them, all nods and smiles, but no signs of comprehension. Like ChatGPT.
You have no basis for your assertion, it's just classism. You seem like some sort of cartoonish basement-dwelling weeb. You're not mr. fucking spock, get over yourself.
He is literally the nicest man I know, and smiles ear to ear when he talks about his kids. This says a lot more about you than my pipes guy.