He is free to say whatever he wants . at the same time, as in any place in the real world, people are free to disassociate themselves from him because of his opinions and comments. Including promoters, sanctioning bodies, arenas, television networks,sponsors or anyone else who might employ him/cut him a a check.
As long as we don't have to hear more bullsh*t about how the world's against him because he doesn't understand the concept of consequences, he's free to preach, I suppose and people will just ignore him. He thinks that by mimicking Tyson's tirades in his post prison career, he's boosting ticket sales but he doesn't have the talent. No one will show up to see him talk crap and then feint for the majority of 12 rounds.