Both socialism and capitalism are real. Socialism itself on the large scale is undesirable and impossible. It can be approximated on the small scale (say less than 20 people) in a very tight nit community (e.g. family or tribe) where there is strong social pressure and environmental pressures to pool resources and help each other, but the moment the community grows so large that you do not know and interact with every single person and do not have a strong bond with every single person, the community fractures into factions, with some factions dominating over other factions and eventually become the elites with special privileges ruling over the plebes which have privileges at the mercy of those in power.

Capitalism, OTOH is simply a system where there is a free exchange of capital which is anything of value. The main critique he has is that because there is no absolute free exchange change of independent value, there is no capitalism. This is the same mistake people who don't believe in free will make. Yes, there is no absolute free will. I cannot will myself to be on the sun drinking ice tea with Socrates. But that's not what free will in finite entities means. It means, given the limitations of your circumstances, you can make a choice. If someone paralyses you and puts you in a sensory deprivation tank, you can still have more free will than your captors since you can choose how you react to your circumstances.

Similarly, most hard assets depreciate in some sense. Rice is a classic store of value, but pests can get to it. Gold and silver wear out with time and their value changes dependant on availability and speculation. Fiat deflates. Properties depend on the ability of you to protect it and environmental factors. Yet all can be considered assets despite their imperfection. Similarly, all trade has restrictions. I can't send some property in the Sahara to the Caribbean. I might transfer "the title" between people of these countries but I cannot guarantee that anyone accepts such transfer as legitimate. I can't easily transport a large quantity of gold or silver or any commodity including fiat with there being a risk of confiscation by either thieves or governments. But to the extent that I can have and transfer value, there is capitalism.