Literally our only evolutionary advantage over other animals is our social intelligence and our ability to work together towards common goals. Our intelligence and our ability to make primitive tools isn't what made our species be able to survive a harsh wilderness with predators that are far stronger and more deadly than we are. It was our tendency to form communities and work together that led to our status as the dominant lifeform on this planet, for lack of a better phrase.

Individualism wants to enjoy the benefits of that collective work while not admitting that they owe any debt to the contributions that made their individual success possible.