In my opinion, it's not so much the clothing itself, at least the outfits I saw didn't look too terrible, it's more just that they're calling it lingerie. Call it almost anything else, and you have a maybe line of clothing that's probably a little more "sexy", for lack of a better word, for little girls to be wearing. But once you call it lingerie, you're automatically bringing the whole thing to an entirely separate level of wrongness.