That depends on what you consider acceptable.
In European countries it's been common for people to avoid those from certain backgrounds even after several generations, e.g. job, rental application, visiting communities.
Also the goal for people to learn and accept others' cultures has completely failed, as far right is on the rise everywhere and western people as a whole have become a lot more critical, intolerant of cultural differences and moralized everything not only in their countries but all others', e.g. insisting on women being equal or homosexuals being accepted as universal rules, which will only make future integration even harder.