The text reminded me of the foreword to Gibbon's history of the Roman Empire. Gibbon complains about esteemed historians who quote other esteemed historians, but never go to the original sources or collect raw data.

A few hunter-gatherer peoples still exist and have been observed by anthropoligists. Are those peoples actually healthier and and have lower mortality than modern Andorrans? (I'm just picking a country at random here.) Or is there some reason to believe that they would have been healthier, if the modern world did not exist?