It has nothing to do with aesthetics, it's a matter of how women are depicted in fantasy, and the real world attitudes that depiction dovetails into. People bring up realism because it brings up the logical question "why is this character dressed this way". If you can actually come up with a logical answer, like that as an inhuman fiend who's entire gig is seduction of course that succubus is going to go around half naked, it's fine. If your only answer is "because boobs", there's a problem, and it's a pandering problem.