With his style (both the way he fights and his constant retirement) I can see Floyd fighting until his mid 40's still dominating opponents and rank in the top P4P category. If he does this he will surely eclipse Pac in the ATG rankings. He'd be the first boxer to dominate boxing for three decades. I can see Floyd in 2021 telling reporters "Who dominated boxing for thirty ****ing years? Answer, NONE".
If he is still fighting in 5-10 years.. It will be after a couple of losses.. I can see him getting hurt like RJJ eventually and continuing to fight on with some ugly losses.
I Dont think Mayweather can fight into his 40's Hopkins is a different fighter that is crafty and pulls out the wins, Mayweather relies on speed and reflex, Im even wondering if he still has it left in him against ortiz because hes going onto 35 soon.
If Floyd still has the desire I think he'd break Nard's oldest boxer to win a championship record. Supplements/Drugs/PEDS will be better in 5 years time and Floyd will still be fresh in his 40's.