How can communism work if humans are so innately evil?

How could any society work if that is the case?

I mean
If its the best looking system on paper then why would the various other systems that look awfully on paper like capitalism work better?

Surely a system which encourages immense inequality would only exacerbate the problems brought about by human nature

Ultimately this would be a flaw with all societies if it were true. The only way a society can function is if at least a certain threshold of people aren't actively trying to destroy it. This is true of capitalism as well.

humans are evil which is why we need a fully automated voluntary state taking care of all our decisions

Humans do what they are conditioned to do, what that conditioning is varies immensely. Whether that conditioning is a product of their environment, social relations, or what ever. Most individuals today, who abhor the way Nazi Germany demonized and slaughtered numerous groups of people so many years ago, would probably support it if they were in the same boots as the German civilians of that time. Likewise, the opposite is true, were the same Germans who supported the Reich modern folks, they would, by and large, think quite negatively of that bit of history.

Some people do seem to be born with a stronger sense of self than others, those who are willing to break the mold despite being raised in a common environment. And innumerable little decisions and coincidences too, will influence one's outlook on life.

How can innately evil beings produce innately good concepts?

You haven't even defined your good and evil, essentialist style nor consequence style (was the act considered "socially evil", etc.), so there's nothing to argue for or against, but beyond that: if human being critters aren't innately good, why do you think they are automatically innately evil?

Either you're trolling, or you're stuck in a bubble in your head.

Not OP, I don't think they're innately evil unless they're predefined as such.

and who would make it?

The Divine Presence.

nanomachines, son

Source of the illustration?

Nothing is innate or inheritly like that.
"Humans" are not a monolith.

Humans in general are not evil
They are sheep that fear pain so in the presence of a psychopath and his army, they will bend and do whatever they have to to avoid being tortured and punished.
People are generally self-interested and their loyalties to others decrease the further away from their family and community one goes. BUt if they meet someone with whom they can engage in mutually beneficial trade or cooperation, they can build relationships.
Systems such as religion can help people think of others even when they have nothing immediate to gain.
Communism is such a failed experiment. Just let people be free to make their own living. The results of trying to make everyone march to the tune of the central planners always ends in disaster and bloodshed. It's mostly a ruse that confiscates wealth from the majority and redistributes it to the people at the top. Who polices the 'party'?

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