It's money. The profusion and success of various streaming platforms mean that Floyd can make millions fighting some youtube idiot. This youtube fucker who I would guess has zero boxing ability based on a couple of circus show fights is currently one of the biggest earners in boxing with the ability to make far more money per fight than most world champions. Tyson and Holyfield are about to make millions. You can't blame fighters for seeing if they can make millions for a glorified sparring session.