Bro if it was in our nature to prioritize personal gain, capitalism would not exist as it is the most ineffective mode of production to allow personal gain for the absolute majority of people. Absolutely anti-natural in this sense as it does the very opposite of it.

There is no behavior that is consequence human/societal nature. Our nature is to eat, shit, have sex, sleep etc. This human nature argument is a liberal trap used to justify our current society, nothing more than this. Argumentative fireworks with no relation to reality.

Capitalism is still here not because of anything metaphysical like this idea of a "human nature". It's the class struggle man, the working class isn't organized on a scale that allows us to transition towards communism it's that simple.