Oh, yes. Basilio hated his guts his whole life. There's also the story about a sparring partner (forget which one, but a member of the Murderer's Row) that kicked his ass on the street because Robinson refused to pay him.
Basilio said he hated SRR but there he was at Robinson's retirement bash. Maybe he was forced into it but I take a lot of what fighters say with a grain of salt.
Leonard had a fake pretty boy good guy personality while being an alcoholic, drug addict and a deadbeat dad who abused his wife.
Winning with a blinding speed that the opponent can't match might make some feel that he was winning because of having an unfair advantage.