you don't need to know him personally to know that he's a dickhead. spitting at people, verbally abusing umps in so many of his matches, verbally abusing his box, domestic violence allegations, almost hitting a kid when he chucked his racquet on court. there's a video of him on youtube just chucking his racquet out of the stadium onto the walkway where there's tons of people walking, so you can't even argue that he didn't mean to almost hurt someone by smashing his racquet in other instances cause he obviously doesn't care. he had no visibility and had no idea if it would crack open someone's head but he did it anyway.

it's one thing not to judge a stranger, it's another to totally ignore when someone is obviously an asshole.