Of course he isn't. Last time he had a proper match was 11 years ago and he ended up tearing half the muscles in his body. Now he is a couple months shy of turning 52, hasn't been a full-time wrestler since 2002, and also has an obscene amount of roided muscle mass on his body, which won't help with either protecting his muscles, tendons and ligaments during a match, or his conditioning.
Punk needed several matches on a weekly basis on his return in 2021 to get into a good enough ring shape to do high-end main event matches, and even he cannot seem to go 2 months without injuring himself anyway