I disagree that it is human nature. At least not generally speaking.
There are people who are innately competitive. And there are people who don't care.
I'd argue that a lot of people are apparently competitive because of social pressures. You'll have to discount the effects of modern society on people's minds before you could make a claim on what human nature actually is like.
Modern society only exists because pre-modern people were so competitive. While a minority might not care, the majority of people in every society constantly compete for status. Always have, always will.
There are people who are innately competitive. And there are people who don't care.
I'd argue that a lot of people are apparently competitive because of social pressures. You'll have to discount the effects of modern society on people's minds before you could make a claim on what human nature actually is like.