Up to about 89, I would not count Leonard out against anyone. However by the time he faced Noris he had goten old. I don't see any reason to think Mayweather has goten old. Mayweather wins pretty easly.
I've heard a few people make this comparison, but you also have to realize that Ray Leonard, during his retirement, struggled with a lot of substance abuse which ultimately effected the way he aged as a fighter. Floyd Mayweather is better than a 1991 version of Ray Leonard and if the two were to meet I'd favor Floyd by decision. Towards the twilight of Ray's career once the speed and reflexes started to fade we seen him take a lot of shots that wouldn't have touched him in his prime. Norris and Camacho tattooed Ray with combinations and Floyd would have done the exact same thing.
Those two had a significant age advantage though. We haven't seen floyd tattoo anyone with combinations in quite a while. Both have taken breaks for extended periods of time, with Leonard's being longer, but he had been keeping in shape in the gym. He's still very mobile and has his combinations, just isn't lightning fast in that fight. Edit: didn't notice the first part, which is a solid point
Prime Leonard beats him, but not as easily as you might be thinking. he would definitely be one of his tougher fights.
Floyd probably...Leonard was an older 34 because of the lifestyle he lived. Leonard got his azz kicked by Norris (and his sparring partners, I think?), at this point he looked severly dimished. Floyd is sharper at 34, but is also facing a huge size disadvantage here.
Probably the only time FLoyd has a chance against Leonard is from his last 2 fights. (Well, he looked pretty bad in the third bout with Duran as well).
