Eh, don't underestimate the savings from reuse that's actually practical and not cost-plus. I think SpaceX have demonstrated the economic case for their approach with the F9. And once SpaceX demonstrate they can put cargo on Mars, NASA'll have to get in. Plus people may actually pay to migrate. If you think those numbers are unrealistic, look at SpaceX's posted total costs for their rocket development programs. I think the message is more "every space agency has ridiculously overpaid for decades."