Emily Yoshida makes a subtle argument for the changing political context of art:
Japanese audiences, unlike American audiences, don’t understand Motoko to be a Japanese character, just because she speaks Japanese and has a Japanese name. This speaks to the racial mystery zone that so much anime exists in…
Of course, it’s a different issue for Japanese Americans… For us, anime is something from our country, or our parents’ country, that was cool enough for white kids to get into just as fervently.
In summary: Japanese artists chose to draw protagonists with non-Japanese features. Said characters became popular in the U.S. where they are treated as Japanese characters. Should the actors chosen to portray those characters represent how they were received or how they were conceived? If both conditions cannot be satisfied, which audience is more important?