Experience does take you a long way, but youth sometimes does overcome. Floyd skillfully is a craftsman, but father time eventually catches up. Canelo is a bigger, stronger guy who's not slow by any means. Sure, he does get hit more than you'd expect, but I don't think Floyd would be as willing to stand in the pocket with Canelo as he did with Cotto (who made it tough for Floyd to keep his distance).
IMO, Trout may be a tougher fight for Canelo physically and stylistically, even in a loss to Floyd.