I’ve seen the same thing as you’re describing, people living in a foreign country and failing to assimilate - at least through language, but I also know others, who are far more ambitious I believe immerse themselves in a language and learn it well. They took the opportunities freely handed them out n university reading groups and such activities, they actually took extra steps to learn both the written and spoken word. They still had accents, but they could intellectualize. It takes effort and many do not want to put in the extra effort is what I think it comes down to- that and who you or they might surround themselves with- people who value or don’t value clarity of language or not.
I’ve seen the same thing as you’re describing, people living in a foreign country and failing to assimilate - at least through language, but I also know others, who are far more ambitious I believe immerse themselves in a language and learn it well. They took the opportunities freely handed them out n university reading groups and such activities, they actually took extra steps to learn both the written and spoken word. They still had accents, but they could intellectualize. It takes effort and many do not want to put in the extra effort is what I think it comes down to- that and who you or they might surround themselves with- people who value or don’t value clarity of language or not.