I'm an Asian American but I find that many people in Vietnam on dating apps are looking for older white men, specifically sugar daddies, so some of it could be a money thing. Tried the sugar daddy thing, didn't like it. Although, I definitely was getting more hits from older white men when I was younger.
And up until 4 years ago, I was attracted to everything but Asians. Come to find out I was looking in ALL the wrong places lol
FYI my husband of 8 years is black so this is definitely not always true