>>109492551. Time passed him by.
2. The single biggest reason a particular wrestler isn't over is because either bookers (probably bookers) or wrestlers do not know how to handle characters in the long run. CM Punk was at his hottest during the summer of Punk and back then his character was fresh and compelling. Everyone was behind CM Punk. He broke the status quo, and if you watched back then you'd know wrestling was terrible for a long time before Punk got to the top. His promos were legit good and funny. IIRC he was the first person to beat Super Cena clean. Twice. CM Punk was pushed as a God amongst men. It was impossible to fuck it up. In AEW he is a guy. His promos are nothing people care about. If you just started watching AEW and saw CM Punk you'd wonder why is everyone so hype about this dude. He also has no dance partners (except MJF, but that didn't go anywhere). We are watching Phil Brooks in AEW, as opposed to CM Punk in WWE. It's like reading Superman all your life and 10 years later now all they print is about Clark Kent.
In short - the reason people used to love Punk is long gone.