Or for some imagined alien species... for humans, however, it could never work.

Pure unfettered capitalism is equally unacceptable... for many of the same reasons.

No system that allows a single person to acquire 100's of billions while his fellow citizens starve should be allowed to continue.

No system that allows the wealthy to buy control of politicians is ever going to be just.

I do not know what an ideal system would be, but I do know that humanity has only 'progressed' away from it. We long ago passed the exit for that utopia, and those that are now driving the bus have no plans to turn back.