I was thinking about it, and I can actually envision it. But I bet some people would HATE it. The character suits his style though. He has clauses in his contracts where he can never lose a fight, he can never look bad, ect ect ect. And that’s Superman in a nutshell. There’s no stakes, because he never loses. It’s right up his ally.
I mean, I kinda liked him in Black Adam. (Though, full disclosure, I’m not familiar with the comics at all. So I don’t have any opinion as to whether the movie is faithful to the comics.) But from what I’ve heard he was kinda such an asshole while filming that WB (which owns DC comics) has sworn off of having anything to do with him again. So I doubt Johson will appear in any DCCU film (or any DCCU 2.0 reboot film). Let alone as so high-profile a DC character as Superman.
But even if I liked him as Black Adam, I don’t think he’d make a good Superman.