I always found Punks theme choice interesting.

The whole song fits who he's become, or maybe always has been

A known narcissist with a group of fans that think the world orbits him, he is pretty much a "cult of personality" and the song very much fits. Turns out he might be one of the few narcissists that know they are one.

Heck, his first run through WWE with the Straight Edge Society seemed to play into the whole cult thing.

IMO it's always kinda been a "oh people think I'm a narcissist but I'm really not, I just play one" from his perspective, but from everyone else's it was "you sure go full method on that performance though".