Maybe he's totally financially independent and just wants to chill instead of writing reg y x ceo doinksize papers
Very possible. And frankly if that's the case, I bet he had a way better time doing his PhD than many of his classmates. And he'll probably enjoy his career a lot more as well...
I wish him the best of luck, as I do the rest of his classmates. Academia is rough and I tip my hat to those who make it but also those who choose not to go down that path.