Name generator follow-up question

Today's name generator question got me to think of this one since I wasn't following wrestling in 2005.  How come CM Punk got to keep his name and gimmick while Daniel Bryan, Seth Rollins, Jon Moxley, etc had to change theirs?  Thanks.
He had Heyman on his side and he was a shrewd negotiator, apparently.  That one's still puzzling people to this day, in fact.