Asian Americans and native Asians "look" a bit different.nature versus nurture, yada yada yada.
Ehh... that's pretty deep... ok life style and culture can affect a person's look and appearance, I can agree. It's also easy to note difference in makeup, fashion, mannerism. Fuck, even how a girl undresses, touches herself, takes a cock, moans and climax (real or fake) is very different between Japanese and Chinese.
OTOH, the external appearance of both average and adult industry Asians has evolved very much in the 20+ years I have been watching porn. They are getting significantly taller and bustier, to say the least. The average skin color and skin condition has also changed significantly as more and more people (both guys and girls) stay away from the sun and moved to a more gentle lifestyle.
So some of that Asian Americans are visibly different from native Asian is also diminishing since native Asians are starting to live lifestyle more similar to N. Americans.
In general, non-Asian Americans (still) have a sort of convoluted view on whatever is "Asian" ... a mixture of that native Asian look with some Western features. Essentially they want that "skanky" look
Well I am actually a big fan of plain and simple mixed Chinese-Caucasian or Japanese-Caucasian blood. Maria Ozawa and a few others... just exquisite. But what you talking about and let me try to rephrase it... is a certain sub-type of Asians that fit some American's stereotype view of Asians.
There's also a historical factor: until recently the stereotypical view of Asian women is that of whores working servicing the G.I.s in Vietnam, Philippines and Okinawa. I remember as an (almost) underage kid sneaking into the sleazy magazines and video shops (VHS!) in downtown New York (that was way before Mayor Giuliani) and the Asian porn section was a disaster zone of ugly. Short (sub-5 feet), dark skin (in a bad way), no figure to speak of, even the hair is bad (not talking about style, but in a bad condition) the women just scream "human garbage" to me. Regarding Vietnamese, I am no expert, but I have seen a few stunning beauties but these whores are nothing compared to them. I have also seen more than a few ex-G.I. (or look like ex-G.I.) both on state-side and over in Asia who have a little Asian woman hanging on to them. Well the guys were older (50+) and the women might be younger, but no matter, these girls were definitely not the most desirable ones by Asian standard.