#2. Commentary
Wait, wait, WAIT. Hear me out on this. I have somewhere I'm going with it.
Think back to WrestleMania VII, when "Macho King" Randy Savage lost a retirement match to the Ultimate Warrior. He transitioned for a while to a commentary role (alongside Vince McMahon and Roddy Piper) - until Jake "The Snake" Roberts attacked him and Elizabeth at their own wedding reception. It took Savage getting bitten by a cobra (literally) to bring him back to the ring.
Oh, by the way, do you know what happened at the next WrestleMania? Savage defeated Ric Flair for the WWE Championship.
Picture this: AJ Styles returns to WWE television. He's not been forced to retire like Savage was, but the experience of both the Boneyard match and being buried alive has psychologically made it nearly impossible to get back in the ring. He loves Sports Entertainment and he loves WWE, though, so he's more than happy to provide his years of experience to the betterment of the commentary booth.
And that could go on for a few months - until someone presents a challenge that he simply can't ignore. It could be someone threatening his family in some way - as we saw in his WWE feud with Samoa Joe. They could make up something shameful in his past and have someone threaten to reveal it if he doesn't face them in the ring.
Whatever the reason, AJ Styles' return to the ring can be built up as a big deal. Plus, a couple of months working the commentary booth would give the Phenomenal One a chance to stay in the spotlight while healing up some old wounds.