I don't know but something triggered him. The way he mentioned those heavyweights of the past and said Marciano's 14st, someone probably said "you should've fought like Tyson/Dempsey/Marciano."
He lost his shit and thought you want Tyson? I'll show you Tyson! Threw the belts out the ring, squared up to someone, stormed out of the ring, squared up to someone else, stormed back in the ring, told Usyk that he's not strong but won because of skill, grabbed the mic and said some random shit, drop mic, cry at the press conference, wraps up another eventful evening.