That's literally made Watchmen so interesting.

It's also why people like Deadpool, and were so disappointed with Hancock.

They are always watching, searching for wrongs to right.

Superman (at least in the old movies and the 90's TV show) actually wasn't. He wouldn't superhero all the time, to prevent everything bad that could happen. Superman only showed up for the big stuff. Because Clark Kent has a day job and personal life. Superman, his alien powers, don't define him. Yeah, they're traits he HAS, things that make him special, but they'd set him apart from the world he's trying to be part of.

He's a reporter, dating Metropolis's famed columnist-reporter Lois Lane, cares about his adoptive parents, and occasionally helps the world out when he thinks it needs it and he can do it with a veneer of plausible deniability to his alter ego.

I don't think the superhero genre started this way at all. After all, the vast majority of silver age heroes were white, straight, male, and morally Christian. These IPs were wrested away from their creators by big business, who then handed everything off to radical leftists. They proceeded to subvert and destroy, slowly at first, and now rapidly, as is their MO.

I also think the classic vigilante is more akin to a monarch; they both decide and enforce a morality that is individually determined, a perfect reflection of their personal worldviews. Only in recent times has the vigilante become a mouthpiece for leftist statism, and that shift has been simultaneous with the overriding narrative switcheroo by leftists. To wit: they must imagine and conjure threats and oppressors so that leftism can maintain the "resistance" high ground even as it mercilessly wields near-total control.