I'm very much with you on the cost-benefit of space. I think with every dollar, we have to ask, "Why not invest this in education?" and "Why not have the public fund this?"
For the former, I don't have great answers, and I struggle with it a lot. With the latter, there is an answer - neither public nor private equity markets have a long enough time horizon to sustain high risk investments for such a long time frame. (Especially if it's, "How do save the species in 200 years?" types of questions rather than space tourism) If it's important enough, we can't count on benevolent philanthropists.
For the former, I don't have great answers, and I struggle with it a lot. With the latter, there is an answer - neither public nor private equity markets have a long enough time horizon to sustain high risk investments for such a long time frame. (Especially if it's, "How do save the species in 200 years?" types of questions rather than space tourism) If it's important enough, we can't count on benevolent philanthropists.