I don't think they hate on him. The biggest thing i've heard was Max Kellerman after the Williams fight saying how Margarito took half the money to fight Mosley he would get from Williams.

First Max is a tool in my opinion. He's got some knowledge but he seems to have an agenda in his interviews and post fight comments.

Second, Mosley is a better name, and on the way out in his career. If he is confident in winning you take Mosley now, and let the Williams fight build cause he's young and gonna be around a long time.