It can be argued that either of them can be more exotic than the other, but the joke is whether exoticness is considered countable. If it is, then because Asians are greater in number, it makes an American more exotic for than an Asian. I'm beginning to sound like guest_.
That's not how being exotic works. Outside Asia, Asians are exotic, and outside America, Americans are exotic. It about being foreign, not rare. If we're just talking in terms of general global population then neither of them are exotic because neither of them are foreign to Earth.
Very funny show - would definitely recommend