Herein lies the actual crux of the issue with communism.
Humans are NOT wired psychologically for it.
I don't understand how people can use this arguement, knowing fully well humans defy what we're wired to do constantly, psychologically and physiologically. Maybe animals compete to be the best, but we've shown time and time again we don't need to obey these sorts of rules. We've kicked nature in the ass endlessly, we're even knocking at immortality's door. It's not too hard to imagine, what with all we've done, bending our true nature again until we adapt to it.
It's quite easy. The human race is a kind of house divided-- On the one hand, we have this fantastic capacity for logical deduction, and rational action; and yet, at the same time we speak out of the other side of our mouths, and assert that some things are so innately biologically intractible that we cant reasonably expect people to act rationally.
Take for instance, the issue with say--- Teen sexuality. Rationally, we realize that teen sexuality is not just bad, but has basically no real redeeming societal value, and causes a net burden and strain on the society-- And yet, rather than take truly aggressive action against it, we just accept "It will happen, they cant control their hormones".
Either humans are rational beings, able to subvert these kinds of drives and behaviors, or they arent. Some may be capable, some may be incapable, and still be humans. that is not a foolish place I will paint myself into-- Rather, it is when measured over the whole sum of a population that prevailing trends happen. Some teens have no issue with abstaining from sexual activity until they are economically situated enough to responsibly partake in that activity; But most won't, and havent historically been able to, even in the face of aggressively restrictive policy. This kind of thing alone indicates that your argument to the reason-ability of the human race is not workable. While some individual humans may be capable of engaging in true communism, the gestalt whole is not able to.
This is demonstrable by every attempt that has been made at implementing it. It always goes down the same path-- Somebody has to assume the role of overseeing distribution, and there is nobody that can reliably be counted on to ensure that this new demographic, with it's expanded availability of resources, will not exploit that availability, and transform the communist society into the false, horrific communism we see historically.
It may be theoretically possible that something unfeeling, like a computer or some similar unliving decision making algorithm could help with this issue, but that just adds a layer to the onion-- Now you have to trust the programmers and system administrators.
Ultimately, statistics is what comes down to the problem. The basic rule behind why statistics works, is that if you have a large and noisy dataset, and select an arbitrary sampling from that population and measure it, the distributions in that sample will be consistent across the whole.
So, if you have a large population that consistently has this problem, the same statistical spread will be present in a smaller one.
If you cant trust the resource distributors, you wont be able to trust the programmers. You wont be able to trust the administrators. You wont be able to trust the general public. Statistically, the humans in the equation are what are unreliable.
Humans are wired for self interest. You can see this trend very prominently when you look at the huge disparity between reproductive childbirth, vs rate of adoption, across all human populations. (this way we eliminate regional noise from specific national or ethnic backgrounds, and avoid having biased data.) You will find the same with reports of child protective services issues reporting with adopted or foster children in relationship with the kinds of relationships they form with their adoptive/foster parents, vs the relationships those same parents have with their own biological children. "The wicked stepmother" is a stereotype; no question-- It does not have difinitive predictive function for any specific individual sampled from the population-- but it does represent an outstanding bias against natural mean. That's why it persists as a stereotype.
More often than not, humans will choose self interest, over communal interest. That is why communism wont work with humans, at least as they currently exist.
[Amusingly, it is also why the tradgedy of the commons is intractible, and why we need law enforcement to begin with.]