Your suspicion may match the truth. I don’t know but I doubt it. I doubt it because human beings have been shown to be ‘social animals’, i.e. animals that naturally form groups which work cooperatively to ensure their survival. Individuals who by nature don’t fit in with the mores and traits of the group or who are, for whatever reason, rejected by the group are generally expelled from it. Rarely do they survive on their own. I therefore don’t consider insularity to be a common characteristic of “human nature”. There are other factors which mitigate against this, too, but it would be over-kill, I think to have that discussion here.

I do agree that the issue is a cultural created and reinforced state, however whilst it is most dominant in developed western nations, I don’t think that it is any less an issue for wealthy eastern nations of for the Majority World.

My view is that it is capitalist ideology and materialism that cultivate the selfish, self-serving, myopic culture that is extremely counter-productive, even highly obstructive to the development of true community and collaboration for the common good. I also believe that this is not difficult to evidence as long as one is not fooled by simplistic, simply false or skewed definitions of capitalism, communism, oligarchy, Left and Right, as well as many other such politically loaded terms. State capitalism, for instance, is as destructive for most as is individual capitalism. Extremism of the Left can be as destructive as extremism of the Right and so forth.