People would have hated Duran, especially after No Mas.
Leonard would have been called a ducker, and people would have said he avoided Hearns for damn near 2 years, Hagler for 3-4 years, and straight up ducked Pryor.
Frazier would have been Foreman's left overs to the Ali haters, and Patterson would have been Liston's left overs.
Larry Holmes would have been fighting nothing but bums aside from Shavers, Norton, and Berbick, and than Spinks when he lost the title.
Rocky Marciano would be a cherry picker fighting old greats like Louis, Charles, and Walcott, even though 2 of those 3 could still fight at a high level when Marciano fought them.
Every single ATG would have had a big fan base and a big bunch of haters. I think people would have gotten more involved in the boxer's personal life like we do today and that either creates fans or haters.