You don't think it is easier to socialize with people with similar upbringings and culture to you? You don't think a group of people indoctrinated into a society from birth are more likely to share goals and beliefs than someone born into a different one?

Blind nationalism is bad, but absolutely no responsibility towards the society and the people that raised and support you is a crazy take. You're ideal would only work if we had 0 social programs and people were 100% responsible for providing for themselves and their loved ones, including education.