In america before the anime craze, panty shots on female cartoon characters was treated the same as boxers though seen more as cute that sexy. Look at Shirley Temple and how many time you see her underwear. There was nothing really sexual about it to the general audience Until we find out how Shirley was being pushed more and more to be sexual but that's a different topic.
Look at old Minnie Moise cartoons. Her knickers were almost always in plain sight but you thought nothing of it because she's not (generally; not counting /co/ and other like em) seen as sexy. Darla either.