Both were matchup problems during their prime.
Prime Roy was a different tier though. Outclassed some all-time A1 pure boxers like Hopkins, Toney, etc. that have made so many other pure boxers look ridiculous. Those are still feats Mayweather didn’t do, so I think it’s a valid question as I think the best pure boxer win he got was against an older DLH, to which he got lumped up.
Posting a video of Roy getting KO’d well past his prime doesn’t prove anything. I’m just glad Roy isn’t slurring his speech heavy after all the knockouts late in his career. Still has clean speech and no crazy sign of CTE.
As for the fight:
Ray Leonard is much bigger than Floyd, taller with a longer reach, fought at heavier weights and big wins against heavier fighters some of which are Hall of Famers. I’ve said before size and reach don’t win fights, but Ray Leonard’s athleticism, skills, etc. makes it too much.
Mosley’s punch is nothing compared to what Ray could drop and Floyd isn’t hurting Ray like a Hearns, Hagler or Duran so Leonard would gladly exchange and aggressively counter. This is a guy who fought Duran in a phone booth for 15 rounds. Ray would not be scared to take a hit from a smaller fighter like Floyd to land dynamite. Ray Leonard had knockout power for 15 rounds and a jaw to take punches for as many rounds. Leonard’s ability to adjust mid fight and change different game plans was crazy too like against Hearns and Hagler.
Floyd maxed out the Pernell Whitaker framework, but that’s too small a build to fight a prime Ray Leonard. Mayweather literally started out a featherweight and fought many fighters who also were also from smaller weights moving up which is why he had a physical advantage. None of those advantages exist vs Ray Leonard. It’s honestly a mismatch.
Floyd has been staggered before by worse boxers and weaker hitters so Ray Leonard would smell blood and finish whether right then or set something up later. Ray Leonard knocked out a Light Heavyweight champ in the late rounds out of nowhere, after getting rocked himself, the punching power is simply different. Ray got some of the heaviest hands P4P.
Prime Hagler, Duran and Hearns would been the best fighters Floyd would’ve fought. Leonard beat them.