Do they? Personally I can't tell the difference physically. I remember being told the differences years ago, but I don't recall the specifics.
A raised eyebrow is always a pretty good response to that sort of talk. As it's almost always coming from a sort of nationalist silly place.
Are there some traits that might pop up a bit more in Place A then Place B? Yeah. But do 75% of the rest of the traits show up interchangeably? Yepppp.
But is it really that hard to find Japanese American actors?
I don't see why it matters. The character is East Asian, and what they need is someone who looks East Asian (and not uh…a white guy lol). Not someone from exactly the right set of borders within East Asia.
I mean maybe if they needed an authentic accent or something like that, but most Asian-Americans wouldn't have an accent anyway.
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Given how most Asian actors seem to be either Chinese or Korean I would think so.
Yeah, the US never really had a huge volume of Japanese immigration like it did Chinese or Korean. And what flow there was definitely dried up a long while back due to Japan first worlding and stabilizing. Heck even Korean immigration has been drying up for the same reason.