They also discover they don't need to assimilate since every western city, at least in North America, has enough Chinese citizens and community resources where you can easily survive with just Mandarin/Cantonese and minimal English.

There are plenty of Chinese people here in Toronto who have been here for two plus decades and still have very poor English (or feign as much). Because they live in Chinese communities, shop at Chinese grocery stores, and eat at Chinese restaurants.

It's their kids who learn English or the ones entering a work environment where English is used.