Billions of people have been porn into abject poverty and disease and without hope for better, have learned (and in many ways seen and experienced) much less than these space travelers would.
I don't think this is relevant or a good counter argument, we could easily say that both scenarios are less than ideal? Being born into poverty at least means you might have options in life like, you might actually meet enough people to find someone who you actually want to procreate with? What's that going to look like being stuck in what is esentially a small shopping mall your whole life?
I'm not sure how it's consistent to impose your own morals and standards onto others' procreation.
Imposing morals? Trolling?