Brilliance sometimes goes to a person's head. Roger Federer is another good example. Elon Musk too.
The world sets boundaries when folks think they have outstripped the normal ones.
In this case, having watched it, I didn't think it was as terrible as advertised. It wasn't intentional and it really wasn't an angry whack of the ball as described. He was distracted and hit the ball with middling force in that direction while looking another way. I think he was thinking he was directing it to a ballboy out of the corner of his eye. Suddenly realised his mistake. He was immediately apologetic. The problem was it hit her throat when she wasn't expecting it.
For myself, I think his ejection was disproportionate.