Linus Torvalds: The mind behind Linux | TED Talk "I get people who tell me that I should be nice. And then when I try to explain to them that maybe you're nice, maybe you should be more aggressive, they see that as me being not nice."

People intentionally bringing up his niceness as an attempt at ad hominem.

Notice when there is a heated argument, it's because he views himself to be right. In these cases, he is usually correct, and technically, so he feels justified about his position.

Character attacks do not negate technical correctness.