This is the "noble savage myth" dressed up for modern times as the "ecologically noble savage myth".
Colonialism is bad, yes.
But indigenous people didn't "live in balance with nature". Consider e.g. the massive ecological changes wrought by indigenous Australians, Easter Island, NZ Maori, etc. Megafauna extinction, massive deforestation, etc.
Human beings are human beings, regardless of their level of technological progress.