RJJ was so dominant that he made it look as if the guys he was fighting shouldn't have been anywhere near a ring. Even though over half of them went on to hold at least one of the major belts which should count for something. Someone also said some bullshit about RJJ not working hard in the gym or being as good defensively.

Who was the last fighter to go an entire round without being hit? Roy Jones Jr.
Also I think you can count one hand how many times Prime RJJ was hit flush.

Not working hard in the GYM? Nobody stays p4p 1 for as long as Roy did without putting in serious gym time. But that's irrelevant to the question because no matter how hard one works in the gym, both pac and floyd would be kayoed inside of 6, p4p vs RJJ because he had way more power and speed.