As someone who has spent more than a few nights in Chinese karaoke bars, let me have a quick laugh at the idea that Asian men are more “respectful, humble, modest, and responsible.”
In my ample time hanging around western men in China and the young women who date them, it’s my experience that women in (inland, relatively poor) China consider white western men to be less likely to cheat, more likely to take an active part in family life, and generally more likely to be an attentive partner. Chinese social spheres can be very separate for men and woman, and often its women who end up with the short end of that stick. The western model of marriage, with its emphasis on emotional intimacy, shared interests, and mutual decision making seems positively enlightened compared to more traditional Chinese marriages. The promise of a high potential salary and a potential visa sweetens the deal considerably. Height is also extremely important in what Chinese women look for in men, and western men often have an advantage on that. Indeed, a lot of the western guys I knew in China were short enough to have a dating disadvantage in the west, but not in China.
The black guys I knew in China- African and African-American/British- had no problem getting girls. Women are curious, and dating a black man was an attractively modern and rebellious thing to do. It would probably lead to more problems, though, when it came to meeting the parents and marriage. I’ve seen it happen, though.
Its my understanding that in China, the extremely serious responsibility to carry one the family line resides in men, so men have a lot more pressure to marry an “acceptable mate,” and there is often resistance to Chinese men marrying foreigners. Women, on the other hand, have always been raised with the idea that they will be married out to “someone else’s house.” It wasn’t that long ago that girl children were considered pretty much worthless things to be pawned off as soon as possible to whoever made the best deal. So parents aren’t quite as concerned with the marriage choice of females. As long as they are married to someone, the parent’s work is done and the rest is the male’s parent’s problems. Boy children, however, have the sacred responsibility to pass down the generations of history in a family.
That said, these are old ideas. I know quite a few Chinese men who have married western women. I will grant, though, that many of the western women I know who dated Chinese men eventually found that said men had serious Chinese fiancees. I think a lot of guys are curious about western women, but still feel a lot of pressure to marry a “proper” wife.
I agree that people are often attracted to the exotic. I think the difference in beauty standards makes a lot of room for people to find "ideal’ mates that would not be considered ideal to someone in their local milieu. For example, in China, skin whiteness is the number supreme above-everything mark of beauty. The saying is “white skin covers 1,000 flaws,” and a girl with ruddy skin will have trouble dating no matter how otherwise desirable she is.
In the west, we don’t have that same idea. So western guys see these women who they see as gorgeous who are inexplicably unattached. They see Lucy Liu where a local guy may see a swarthy peasant with the big mouth of a farmer.
It works for women, too. Western women are very desirable in much of Africa. You see a lot of plain, chubby western women married to men who look like underwear models. And I’m sure those guys see nothing but beauty in the women, according to their own schema.
Anyway, just some thoughts. I wouldn’t make too much of any seeming pattern. People all basically just want to get laid.