Communism lacks understanding of the human nature. It fails to recognize that humans are sometimes apathetic, vile and corrupt. Darwin's theory does not apply only to evolution pre homo sapiens. It manifests in all of nature. Communism refutes that theory at it's very core and removes the mechanism society rewards individuals for following their instinct. In fact, it punishes them for it.
Communism/socialsm has noble ideas. But those ideas live in a silo. When they touch reality everything shatters.
The problem with your thinking is that you ignore the fact that socialist policies have been implemented successfully in all modern western democracies and somehow those societies haven't shattered yet. It's called a "mixed economy" and you're living in one right now.
The idea that we have to construct a society based on idealistic absolutes is nonsense. Some problems are more efficiently solved collectively, others are better solved by the power of the market. Let's harness the power of both.
If the day comes when AI abruptly puts huge percentages of the population out of work and our society faces collapse, one can easily envision a solution that implements structural changes that incorporates both the benefits of market forces and the efficiencies of collective resource pooling.
Communism/socialsm has noble ideas. But those ideas live in a silo. When they touch reality everything shatters.