I don't agree with the 'lad' all time either, but like his ability to push technology, while making himself richer than Bezos (?) in the process. To advance the species, as important as Mars is, for space, I'd hunt around the asteroid belt 1st, AS a return on investment. Or, of course, do the metallic Psyche-16. 10 quintillion Euros of industrial mineralogical goodness!
For the human race, 3D printing of whatever we need. IF we can do this, K. Eric Drexler's Nano-fabrication, aka J. Storrs Hall, aka Ray Kurzweil. The Utility Fogs and all that may have to wait until the marriage of low-error, quantum computing + LLM's? Counter-opinions welcome.