The ones who died of Type I diabetes, or from an infected cut on their toe, or appendicitis, or other easily treatable conditions, probably didn't. I do know that anyone in a modern society today is free to live a hunter-gatherer lifestyle if he is so inclined, but that few do.
And do you suppose that these hunter gatherers are healthier and happier than people living in the slums of Rio de Jinero? Because that is their choice if they “join society” in their region. Freedom and a healthy happy life in the jungle, or poverty and disease in the slums with an open sewer running beside your shack.
The majority of urban dwellers on earth, even today, do not live like “modern society”; they live in much worse conditions than those eking a life out of the rain-forest.