You're not getting it's not communism that's inefficient, it's humans.

A good country would work fine under a capitalist or communist system because it's just a bunch of good people who happen to prefer one system over the other.

Real countries are into killing and dying and being delusional about fossil fuel.

It also just so happens that communism was the original system and is the only one we've ever had where humans were sorta properly functional. We still all died, but we coped better with it and we weren't finding ways to wipe out the planet (including ourselves). It remains to be seen whether experimenting with other systems leads to more survival or less.