Once again, there are stigmas about the black community dealing with elevated levels of violent crime, poverty, welfare, etc. Black folks making jokes associated with thier own stigma is one thing. Black folks did not get this stigma all by themselves.
But if we were talking about jews who do not have any such stigma, if he went on such a racist rant, there would be no question about if it were racist or not... Just ask Mel Gibson
Any question about his tirade being racist is mind boggling and hypocrytical....