Descriptively Individualism is Communism

"Anarchism demonstrates that there is no contradiction between advocating socialism and advocating individualism; so what stops socialism is not a defence of “the individual”—even if anarcho-socialism would ultimately crush the individual."
@Xenopol

Individualism is a kind of egalitarianism, which is Fascism.

In the end, individualism is about treating everyone identically. As per hbdchick, individualism is a result of manorialism breeding the ingroup to expand. There's no [my clan] vs. [your clan]; everyone is in the same clan, according to the genes of individualist peoples. Distinctions become erased, and you can treat everyone "individually."

Not only are there not McCoy clans and Muhammad clans, there aren't smart clans or dumb clans. There aren't polite clans or deviant clans. There's no benevolent clans nor sadistic clans. It takes tremendous effort for the modern to even acknowledge the Karen clan or the Boomer clan. There's only the "humanity" clan.

Secondarily, in fact it's cognitively prohibitive to treat everyone individually. Even lower nobles only have space for a few broad groups. (More on social simplification.) Individualists don't stop treating folk by their group. Instead, they all get put into one broad group: [individuals], and treated identically. 

This sells rhetorically because there's no aristocratic clan or peasant clan. The peasants eat that shit right up. Nom nom nom sewage yay nom. Equality before the law is about treating unequal individuals equally.

Individualism shouldn't be about this. However, in practice, it is. The wild form of individualism is logically incoherent. This form of individualism is in fact collectivism, but the collective is supposed to include everyone. Since collectivism is pathological, wild individualism, being hyper-collectivism, is hyper-pathological. 

We can see that individualism does indeed assist with tolerating the environment of industrial civilization. Much easier to trade long-distance, for example. However, as with all State interventions (more Church in this case, but still coercive and power-addicted) it's ultimately destructive. At present it looks like all individualist peoples will self-annihilate by diluting their gene pool until the individualism is lost along with the accumulated bonus IQ. 

P.S. States are so inherently corrupt that equality before the law is still better than privilege for superior individuals. Quis custodiet. Although in fact privilege immediately re-appears, precisely because States are inherently corrupt, so more importantly equal justice under law is impossible as long as "justice" is State-supplied. 

P.P.S. I think I can sharpen this point further. Got a lunar path hunch there's a much finer argument to be made. Can't solarize it right now, though.

P.P.P.S. Real individualism is private-individual property, which would indeed stop socialism. As shown by the Owenites in the 1830s (pre-Lincoln!), the commies would go: "Give us your stuff for the greater good," the privately-owning everyone would say: "No? Dude, take your meds," and that would be that.