A socialist vision for space is a great idea but the problem is that the narrow vision of marxism would likely take over and degrade the idea to the level of Marx's reductionist scientism, historical materialism, and purely economic categories. No idea of human will, soul, values and facts, or morality could enter (in fact Marxists are aware of the problems and don't really believe in their own take, but the problem would surface).
The so-called left has no real vision for society beyond the sterile marxist capture of the idea.
But the basic point that capitalism in space is potentially pernicious is a good one, but post-marxists and other leftists need to reinvent the idea, without sentimental pseudo-leftism, but not in the crypto-Stalinist vein of the current left dominated by now archaic notions.

The billionaire space race has perverted what space exploration should really be about: serving society and advancing humanity.

Source: We Need a Socialist Vision for Space Exploration