Barbie dolls are marketed/meant for young girl. It's not entirely the product in question, but who the products are marketed/meant for.
When a little girl is playing with a naked Barbie doll chances are very high that she isn't doing so in a perverse manner. Now, when an adult male is playing with a possibly naked pre-puberty Gundam girl, that's when things get super icky. Not saying that an adult male wouldn't play with a naked Barbie, but Barbies are not marketed towarRAB males.
OK, that's fine then, if the figures clothes don't come off that still doesn't change the fact that they are still under-aged Gundam girls marketed for males who, in my opinion, look sexualized. If you don't think so, that's fine. We will just have to agree to disagree.