Well, this topic really belongs in the Science section. Until GS sorts out the issues on RPF, I cannot move this topic.
The above is a gross exaggeration. For example, the Mongols ate some raw meat, and the Huns(Europeans) who wiped out Rome etc. were famous for eating raw meat and considered barbarians by the Romans for not eating cooked meats.
The sick truth of the neolithic is that it enabled groups of less intelligent people to overcome, through various simple group-oriented strategies, more intelligent (often HG)people in Europe or elsewhere. Take modern times:- the police are well-known to be incompetent and quite stupid people, generally. However, through various group strategies, they are able to outwit the more intelligent criminals a lot of the time, even if the latter planned their crimes well.
Take Neanderthals, for example. They were far more harmonious with Nature than early modern humans and were far more intelligent, yet got wiped out. They had an average of 1600cc brain-size/volume, and, among primates, the EQ(encephalisation-quotient) is not applicable, with the size of the skull/brain being directly related to intelligence:-
https://www.quora.com/In-which-animals-is-the-encephalization-quotient-metric-of-intelligence-most-badly-flawedThe point being that Neanderthals might have been wiped out by disease or by superior group strategies by early modern humans(such as the latter having larger numbers due to previously living in warmer, safer climes).
The point being that civilisations have certain advantages BUT they generally give up their health by going in for processed, non-palaeolithic foods, thus enabling other, more vital, more primitive societies to eventually take over once the former civilisation has too many people with declining fertility/declining health, declining immune-systems(enabling plagues etc.). One only has to look at Ancient China, Ancient Persia, Ancient Rome etc. etc. for examples.Also, more advanced technology/civilisation allows people to better survive who would never have done so in a healthier more tribal age such as the Palaeolithic era. One reason why evolution was upward in the Palaeolithic era was because child mortality was so high due to infanticide etc.(c.80%). That meant that, if a toddler was a bit slow in the head, he got drowned in the river as resources were scarce etc. Nowadays, ever since the Palaeolithic ended, average human brain-size has declined (depending on the source) from 10-20%, with humans predicted to be having the intelligence and average brain-size of Homo Erectus in another 20,000 years or less.
The point being, don't underestimate Hunter-gatherers.