Other than money being the reason for a comeback, what fighter can you see from the current generation filling his shoes and eventually facing Floyd for that 50-0? Crawford, perhaps? Maybe Thurman? If Floyd was to seriously quit, he'd need someone to take the mantle and become the face of Boxing. I don't think that will be Canelo (for all his hype). Who could you see being the best May/Manny in boxing and Floyd coming back to get to 50-0, provided he retired for a good while?
Thurman, Crawford, Lomachenko, Frampton, Ward(still there's hope), Golovkin, Kovalev and Brook are all possible choices. If I have to pick one, then it's going to be Ward if and only if he decides to be more active and sorts out his managerial problem.
Pac will win so pointless thread. Even if he lost I hope noone fills Floyd's shoes as boxing cannot handle another extremely boring boxer for another decade. He can give Memo Heredia and his dirty Vegas connections to Devon Alexander if he wants a successor though.
I think Canelo is going to be the next guy, but if i had to put money on someone filling Floyd's shoes that wasn't him, i would bet on Keith Thurman. 26, well spoken, exciting, has a good platform on NBC, world champion. If he can get people watching him, then I think he's going to be the poster boy for boxing on NBC. Lomachenko has a ton of potential as well, but to be that big star, you almost have to be from America. Pacquiao is an anomaly, there aren't a lot of guys who can get PPV buys that aren't from America, and while Lomachenko is great, the american bias against fighters from Europe might prevent him from crossing over. Hopefully i'm wrong, because Loma is the ****, but I don't think I am.