I've spent about 8 years in Japan. I love parts of the culture (the good parts, not the bad parts). Things like the service ethic, politeness, safety, and the basic idea of "do whatever you want in your private life but don't put out anyone else while doing it."

My guess is that a massive influx of foreigners would likely destroy that culture.

Is there any way to open borders and still preserve a place's culture, at least the good parts, or is that just doomed?