What it can point to is the "superstition" and "prejudice" of Russian and Chinese peasants, i.e. to the same "cause" pointed to by Marx to explain "Oriental despotism" and mid-19th century Prussian and French despotism, to conditions inconsistent with those required for the development of "the real intellectual wealth" of individuals.
Somebody: In *what* society have individuals been intellectually wealthy enough to sustain socialism?
It's been speculated that we could genetically engineer people to be altruistic enough for socialism. It may be that the intellectual development you're talking about is beyond the abilities of a species that evolved to hunt big game in the Pleistocene.