In all 3 of those places he had success, particularly Van and NY. He has been nominated for Jack Adam's award several times, winning once. This is not a guy who can't coach, or doesn't know what he's doing.
Personally, I'm getting tired of players who whine and complain that coaches are too tough on them. These players want to make millions, gain fame and celebrity, and hopefully win various things. Well if you want that, be that! You are being paid to perform for your employer. If I went to work and whined about my supervisor and tried to demand he be replaced, I would probably be assigned to protect a telephone pole in the winter, on route 66