The monkeysphere is the way our minds are wired.
OK, so the monkeysphere is the way our brain is wired.
The next question — at least for me — becomes whether we simply "accept" that as the final answer and say "... so therefore we can't help ourselves," OR do we stay vigilant and conscious our brain wiring and say "these are the ways in which this is not serving us," and take steps to rise above the limitations.
For sure, a post-scarcity economy would do away with a lot of bickering.
Modern neuroscience also suggests that we can, after a fashion, rewrite our neural nets to bypass certain types of thinking/trauma; it requires practice and dedication.
Humans do change, in response to their environment, and it doesn't have to take 100's of years. Take, for example, the decline in testosterone of men in western nations over the part 40 years as a result of technology taking over traditionally "physical" requirements. In a sense, that's almost a form of environmental genetic engineering.
RE: Is "Tribalism" Good, Bad or Indifferent? Is "Us vs. Them Our Strength or Our Downfall?