When Western Style Superheroes Appear in Manga

It's a truism that in manga that there are manga suited to every topic and influence, from playing on a basketball team to the biography of Buddha or Adolf Hitler to manga about preparing food and drinking wine. But one subject area that doesn't seem to thrive in manga is Western style superheroes, at least not in the translated market. The closest analogue to Western superhero comics is the comic MAIL, which was a pretty successful iteration of the supernatural-mystery format seen variously in books like Dr Strange or Constantine. But the book didn't last very long, concluding after just three volumes. A manga like One-Punch Man feels more like a satire of conventional Western superhero comics. Is it that these comics don't exist in either country, or is it that they simply don't succeed in the US direct market because of competition from existing superhero properties? Or is there another, less obvious reason why Japanese superhero comics haven't succeeded in the US market?