When I walk through the streets of a random European or Asian city, I see lots of American brands. I see MacDonalds, I see Starbucks. I see local brands, advertised using English-language slogans. Sometimes using English that would never pass the lips of a native speaker.
Sometimes American culture is so distorted that most Americans wouldn’t recognize it as American any more, but American culture is everywhere.
Americans, however, aren’t.
There just aren’t many immigrants from America in European and Asian cities.
No matter what a person you meet at a McDonalds in Austria looks like racially, they are very unlikely to be from America, or descended from Americans.
So, what’s wrong with depicting a future American city that is on the receiving end of cultural influence for a change?
It’s a future where other countries have taken over America’s role as the biggest and “coolest” exporter of pop culture. Those people from the new “coolest” countries won’t bother to move to the US. And it might be a future where America has become less insular and more open to ideas from elsewhere, adopting and adapting them without requiring immigrants to bring those ideas into the country in person.