#1 If he really wanted to get back in the ring, he would have joined AEW
It was only a few months ago where CM Punk was heavily rumoured to be joining AEW. It seemed to add up since many believed that Punk had gotten the itch to return to the ring and that AEW would be the perfect platform where he can get a big paycheque while also not having to be creatively flustered.
However, he put those rumors to bed when he revealed that his interaction with Cody Rhodes and co was minimal. From the look of things, he seemed to have burned the bridge with AEW after the comments he made. Cody Rhodes told ESPN:
"He did kind of make us look like dumbasses, saying we sent him a text offer. I'm sure we texted him, but we also called him. Someone also met you in a coffee shop. We made genuine efforts. But in this case, 2019, it's been quite some time away from the ring. We gotta focus on who really wants to be on board with us versus going out and finding someone who perhaps doesn't really want to be part of this."
With that said, Rhodes did keep the door open for Punk, but the truth is that if Punk had the itch to get back in the ring, he would have joined AEW. That's why he likely won't be returning to WWE.