Firstly, human evolution is typically not survival of the fittest, but rather survival of the average. Outliers are misunderstood, envied, feared, killed or harmed. This happens to the less intelligent as well as the more intelligent.
The reason this happens to the intelligent is humans are envious and violent and prone to misunderstanding people who are smarter than them. This leads to violence toward, obstruction of, or not helping those who seem more intelligent.
It’s hard to escape a black ghetto because you will be perceived as “acting white” and attacked for that. It’s not very different in white “rural ghettos” (or urban) where intelligence is perceived as a threat. In many societies, average people cannot or will not lend support to their more intelligent members because they know, or imagine, that such behaviors will eventually lead to them being “lorded over” by the person(s) they helped.
Just a few generations ago, Italian American communities were famous for discouraging higher education among their children because it threatened the social structure if sons, let alone daughters, attained better careers than their fathers.
I am sure there are many other subcultures within the USA and throughout the world that have similar attitudes. Siblings often envy and decline helping each other, to say the least.
In the more distant past, violent death at the hands of other humans was a very common way for people to leave this vale of tears. Today the killing is less, but I doubt the harming is all that much less. Nowadays people use rumors, lies, poison, and many sorts of hindrance to prevent intelligent people from rising above them.
In a gruesome but very realistic way, this all makes sense because, evolutionarily, why should an individual help a genotype that is different from their own? This is probably why so much extant human intelligence, such that it is, is devoted to deceiving other humans, outsmarting them, out-competing them, getting ahead of them. Humans do better in a capitalist system because capitalism allows them to compete by virtually any means they can get away with.
Some strongly hierarchical societies, like China, do tend to help intelligent people if they are well-connected or have already risen to the top of a hierarchy. On the way to the top, though, the internecine fighting can be as bitter as anywhere else in the world.
In times of war or perceived threat, many groups will help the smarter ones of their own, but compensate by harming other groups even more viciously that usual. You can see this behavior in some cults, cliques, and secret societies within the USA today. Sometimes they help their genotype and sometimes they help their ideological types by that sort of behavior. In a sense, groups like that are just acting like individuals on a larger stage; they are selfish and violent as a group, but not too bad to themselves.
Having spent so much time with FIML practice and its considerable social and psychological implications, I don’t feel sanguine about the statements above. Isaac Newton helped the whole human race because somehow he was both left alone and helped. Had he spent time in public houses just being himself, he probably would have been beaten, and thus returned through brain damage to the common lot. Had he not been helped, he probably would have done nothing, and certainly much less. My guess is England probably had hundreds of potential Newtons, but just that one survived to produce great science.
Archimedes was murdered by a Roman soldier. Socrates was poisoned. Newton survived. These are the few we know about. I am sure there are many thousands more who were destroyed before they ever did anything to cause us to know about them.
My guess is the Buddha meant something like the above when he described the Four Noble Truths. Notice, that his formula provides no way for societies (large groups) to escape suffering en masse, but only a way for individuals or small groups.
Large groups can become more comfortable but, it seems, always at the expensive of even larger groups that are exploited by them. Maybe computers and machines will fix this problem in the future, but there doesn’t seem to be much hope today. Multiculturalism will very likely make things even worse, except for the few groups that dominate the others. Not much different, except in scale, from a normal bad neighborhood today.