For better or for worse, FOY is not about 1 signature win. Thats the point you seem to be missing. Adonis didnt have the best signature win, and he may not even be the #1 in any unofficial criteria for the award...but he has the best overall case for it (# of wins, quality of opponents, dominant performances, title defenses, etc).
Floyd winning would be a joke. He's only there because he is the face of the sport.
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