I suppose the important bit is really that there's universal buy in (and with the moon landing thing that was supported by making it a matter of national pride)

I suppose the important bit is really that there's universal buy in (and with the moon landing thing that was supported by making it a matter of national pride). With incremental progress you risk things looking invisible (just like AI is always just the things we can't yet do, while newly possible tasks are merely computations). "Do some notable thing in two terms" monument building exercises risk being shot down on budget reasons when any part of government ends up under new management (see Congress). So I guess you can go incremental (but solve the visibility bit somehow) or grand vision. Right now, NASA seems to be going through the worst of all.