More I think about it, “sustainability” of reusable rockets mostly shifts the problem: launchers save costs, materials, supply chain factors ... but re-entry and delivery of more assets remain non-sustainable for everyone else (i.e., atmospheric impacts).
We jumped to 'could' without the 'should'.
Sums up the oligarch assholes nicely
The thing that kills me is the estimated 10-20 launches required per moon mission.
It seems we're heading much faster towards a Kessler scenario than previously thought. This is where it low Earth orbit fills with so many satellites they start colliding, and the debris field creates a cascading runaway effect, rendering space pretty much inaccessible after that.
Long-term, payload delivery systems should probably transition to non-rocket systems such as launch loops or skyhooks. Both however require substantial upfront cost and in the case of launch loops a constant stream of power. And both have dramatic failure modes. There are no perfect solutions alas.
More seriously on the case of reusability imho, I think there's some ways of looking at the aspect of what was being talked about in the 70s and 80s in terms of being able to repair satellites on orbit, able to refuel them for continued lifetime, or even being able to bring them back a bit.
