Sorry but if you know his story, seen candid videos of him, or talked to the people around him, he's a Linus-level "I'll say what I want" type.
There weird hagiographies need to go. Carmack is absolutely not known to be kind. I have no idea what happened here but the idea that's he's this kindly old grandpa who could never, ever be rude or unprofessional is really out there.