There are a few things to keep in mind: 1) Ariana Miyamoto was chosen as Miss Japan by Japanese people. 2) The critics of Miyamoto are an extreme, vocal minority on Twitter and 2chan. 3) Although Japanese contestants often perform well at the international level, beauty pageants of this sort do not receive much attention within the country regardless of the contestant. 4) "Hafu" is a Japanese word derived from the En…
TBH it's not that different from Korea or China in general, countries I've also lived in. Those 3 nations (ones I can speak for at least) are homogenous, not "nations of immigrants," they haven't had turf wars for minorities, civil rights & political correctness movements. Just the casual daily encounters experienced there as someone who is trying to live there (not someone who is clearly a tourist), would completely baffle any politically liberal, tolerant American.