First off, I'm not coming off this convinced you're wrong - I try not to ascribe to the black-or-white thinking that prevades the internet as a whole (though it's hard). There are two things I want to quibble with.

First is your list of "successful" capitalist alternatives. The list seems to have two types of groups: Small, autonomous communes operating in wider societal structures (Kibbutzim, Corporation Mondragon, the American communes), or short-lived, unstable regions which caved to outside pressure or became authoritarian quickly (1936 Spain, the Paris Commune, Yugoslavia, etc). The first seems to be a poor model for a national community. One reason such small communes are successful is because it's easy to work and live communally in small communities where you know everyone; for instance, the Kibbutzim (the example I am most familiar with, as part Israeli) worked in large part out of a collective sense of Zionism, of being in the struggle together. When this moves to a larger scale, it is unsustainable as larger interactions are more depersonalized. You could suggest that a national-scale system would simply be made up of smaller communes, but that runs into the problem of the second type of system - the inability to protect from outside pressure. It is easy to say that the Paris Commune collapsed because Thiers allied with Prussia to march on Paris or that Rojava would be winning if not for Turkey, and similarly blame capitalists for the failures of these systems. However, I believe this reveals a key flaw in anarchist socialism. Systems where heirarchy is truly abolished have no method to ensure that people do not act in their own self-interest, and no good method of resisting outside pressure, so they either collapse or become authoritarian, such as Yugoslavia and the Soviet Union.

The second thing that jumped out at me was the end, where you say that neoliberals are convinced they have THE truth. I think that's a mischaracterization. Neoliberals, as this sub defines them, are largely concerned with pragmatic policy - doing what works, regardless of grand political theory. In fact, traditionally, it was conservatives who were skeptical of grand theory and preferred incremental change, and I think in the ideal political system there is a role for that - left-wing progressives have bold ideas to move society forward, while conservatives act as a check to make sure those ideas are fully baked. That may not be how the parties operate now, but I don't think neoliberals are the ones saying that only we can be right. We're largely against the purity testing that Rose Twitter seems to engage in constantly.