Not as bad as Larry Holmes or George Foreman or James "Buster" Douglas or a whole lot of truly big men.
Tyson is not a huge man.
Tyson punched a man in the face multiple times a year or two ago on airplane. Man didn't really get hurt.
For the right money, I would box him. My opening negotiation would welterweight. I wouldn't fight him any heavier than light middleweight. If he shed some muscle, he couldn't hurt me much.
Tyson won the fights he won, but he never was a huge 6'3" 265 lbs. man.