Ruin Explorer
Legend
I think you're confusing "shonen manga" (i.e. manga aimed at boys and young men) specifically with "manga" as a whole.Typically, those two approaches to aesthetic and storytelling tend toward very different assumptions about power, how the world works, which tropes are "normal," etc.
This is an equivalent error to confusing "thrillers aimed at aging men" (like Jack Reacher) with "novels" as a whole.
Manga isn't a genre. It's a medium. It literally means "comic or graphic novel". It's incredibly diverse. It's very far from just stories of teenage boys gaining super-powers or whatever.