Me personally, I’m tired of seeing teen heroes, and teenage Spider-Man is done to death at this point. There have been eight Spider-Man movies, and at least twelve Spider-Man cartoons, and Spider-Man has only been an adult in two of them. That’s Spider-Man: The Animated Series and Spider-Man: The New Animated Series.
In the 1994 Spider-Man show, he was 22 because he’d been attending ESU for a while, and that’s at the start of the show. Then, in season five, he’s already married to Mary Jane. In Spider-Man: The New Animated Series that aired on MTV, he was again 21–23. And then he’s 23 in Spider-Man PS4. But that’s it.
The thing is, Peter graduated high school in Issue #28 and then graduated college in Issue #185. There are over 700 issues of The Amazing Spider-Man, and most of his iconic stories—the ones fans actually like—are when he’s either in college, graduated college, or still in college in his mid-20s getting his doctorate or something, because that’s how damn smart he is.
But for some reason, Hollywood keeps putting him in high school. And I also blame Ultimate Spider-Man for this too.
depends on the story you want to tell
regardless, don’t forget about the new Into the Spiderverse animated films which, though feature a teenage protagonist, do liberally include an adult Peter Parker and we see some glimpses into their life and struggles