Plenty of games are anti-capitalist (cookie clicker is the first one that came to mind!) but they are usually critiques of capitalism by demonstrating the issues with it, rather than demonstrating alternatives.

There’s a minecraft mod where villages will give you free resources if you’ve been helpful to them in the past, but it’s quite limited. I agree it would be interesting to play a game where alternative systems are clearly depicted. Would fit well with a sci-fi game.