Pulling this to the red-headed stepchild of the general threads because it is VERY off-topic.
The "civilized urbanite vs uncivilized redneck" concept is 100% universal, as far as I am aware, and has been one of the most consistent sources of conflict in the modern era. I'm not as familiar with the pre-modern period, but from what I know of ancient history (Rome, Greece. Egypt, etc.) the idea may well be baked into our DNA. The rednecks almost always lose out compared to urban populations, too. For example:
The French Revolution's War in the Vendée, and the Reign of Terror it sparked? Killed shit-tons of random rural people in the name of Jacobin (so, Parisian urbanite) ideals. My personal favorite being the hyper-insanity that was the so-called "Temple of Reason" and the subsequent
Cult of the Supreme Being. All of which served as convenient distractions from the fact that urban Parisians had looted rural areas and Catholic churches to pay for their newly enlightened lifestyles. Paris itself lost 1500ish people to the Terror's purges: meanwhile the Vendée lost
at least a fifth of the region's population.
Same with the Russian Revolution. The Bolsheviks (who were almost entirely based in urban areas) took over the workings of the country, and started killing
relatively wealthy peasants called
Kulaks and confiscating their grain and property to fuel their own development. There was a whole system of rhetoric blaming the peasantry for capitalistic resource hoarding despite the fact that most Kulaks had very little money.
There are hundreds-if not thousands-of historical examples of bigotry against rural populations, and "redneck/hillbilly" is just the latest one in the anglosphere. I'm not sure if its because the population undercurrents you mentioned lead to cultural differences, or if its specifically something to do with the urban/rural divide, but you are very much onto something. It's a concept not openly discussed in a lot of academic circles (at least not in the US ones) either, because it has some very uncomfortable implications to it for the highly educated bigots out there.