Where I am (not America, which is where he, and probably you, are making your observations):

• Chinese people (Koreans and Japanese are practically non-existent) are heavily cliquish. Most associate with their own kind and speak their own language except when forced to interact with racial others. It is rare to see Chinese women with White men. Same thing with Indian, actually, who are also everywhere.
• South-East Asian women with White men is very common. Can't go anywhere without seeing them kind of common. This has been going on since the 1970s or perhaps slightly earlier, where various matchmaking services existed in this country with the explicit purpose of matching up White men looking for wives with South-East Asian women looking for husbands. Perhaps the proliferation of WM-SEA women couples is partially the result of this having become a business model. Furthermore, the fact that the women relocate here rather than the men relocate to SEA strongly suggests that women enter these relationships with the expectation that they will be the ones to relocate. I think that the participation of SEA women in such services would be borderline non-existent if the expectation was the reverse, because they themselves would gain much less from importing White men into SEA than being imported into White societies.
• White men who I've talked to without exception claim that they go for Asian women because White women are too 'feministic' (they have never replied by claiming that they find them more attractive or any such thing). It's the usual 'Asian = submissive' idea (though there's also a strong 'Asian = fiery tempered' idea that seriously clashes with the former).

Obviously I have no idea what's going on in America, where the Asians tend to be ethnically different and various communities are probably at different levels of cultural assimilation than here (no Asian community here could be considered even remotely integrated, even SEA women overwhelmingly have SEA friends, including when married to White men). Lastly, I don't believe that women are very visually attracted, so the general appearance of White men (and, indeed, all studies I've read seem to put White men at the top) is likely subordinate to other, more extraneous factors, most notably, access to material resources. Finding a husband is obviously very different to rating pictures of men, which is how those studies operate. Furthermore, stereotypes such as 'Asian woman = gold digger' and to a lesser extent 'woman = gold digger' do not exist without reason—but they would seem to be much more baseless if women did not prioritize access to material resources over other factors.