No, I don’t. This is already the case in many neighborhoods in the USA and the sky isn’t falling in those places.
Also, I live in Germany half of the year, and there most of my neighbors don’t speak any English, and my neighborhood is fine. I don’t see the problem you are describing with your example.
If that’s your “extreme” example, I am curious what your day-to-day ones would be.
Perhaps it’s uncharitable but I am having a hard time seeing how this doesn’t alias to simple racism.
I didn't claim the "sky would fall". I just claimed it would affect you.
I think most would agree that it is easier to form connections with those who are more similar to oneself. Call it racism or tribalism if you want, but that's reality.
It can be a really cool thing too if both cultures open each other to exchange languages and celebrations, but it requires a lot of effort from everyone.
Obviously that's an extreme example, but other cultural differences will affect you as well.