And I'm told that people were twisting themselves into pretzels to make Cho not Asian.
I mean, it's true, the text does not say, "Cho Chang, a pretty Chinese girl..." It just describes her as a pretty girl with straight black hair. Named CHO CHANG, not to put too fine a point on it. I mean, maybe missing it once if you aren't familiar with the world's most common surname, but when it's pointed out, trying to argue that she's a white girl who was adopted by Asian parents? My head hurts. I mean... WHY WOULD SOMEONE DO THAT? It's confusing to me. It's not a detail that makes the slightest bit of difference, so why not just use the canon? Is Occam's Razor really that dull? Why make up a convoluted story to deny the only obvious hint we have about this character's ethnicity? Is Seamus Finnegan assumed to be a Chinese boy adopted by Irish parents? I mean, these are minor side characters who are painted with a broad brush--just enough to give us a couple of details. And we... ignore those details entirely?
As a fic writer, I'll admit that it's very interesting to maybe go for a less common explanation of something's provenance, if it makes the character more interesting somehow. But Cho's race is apparently a non-issue to anyone in the general vicinity, so making up a huge story about it isn't going to make her any more or less interesting than she already is.