I've only seen John Carmack's public interactions, but they've all been professional and kind.
It's depressing to imagine HR getting involved because someone's feelings had been hurt by an objective discussion from a person like John Carmack.
I'm having flashbacks to the times in my career when coworkers tried to weaponize HR to push their agenda. Every effort was eventually dismissed by HR, but there is a chilling effect on everyone when you realize that someone at the company is trying to put your job at stake because they didn't like something you said. The next time around, the people targeted are much more hesitant to speak up.