On what basis could they fine him? Right, wrong or indifferent, his comments were personal and had nothing to do with his ownership. If he influenced the hiring or firing (within the confines of law), is that not a prerogative of ownership?
He has blacks on his team who are well paid. Whatever his views, it hasn’t appreciably affected the employees the public sees in the court. And that’s what matters.
Because he is in breach of contract. Pro sports Leagues have rules/obligations you must follow to be permitted to own a team. Essentially, it’s a club with a contract. They can get rid of you in many ways for “conduct detrimental”.
Free Speech etc does not apply as this is not a government action.