I think you're missing the point that in other parts of the world people (kids, adults, men, women) do read comic books. In those other parts of the world, where comic books are read by all sorts of people, they are not so overtly sexualized as those in the USA.

Maybe you're right that non-young-male-Americans are genetically incapable of liking comic books as a medium, but it seems more likely that Americans are no different from Europeans, and would like comics if they just made comics for them.