I assume your use of the word “investors” refers to Congress approving funding, and is not a reference to private investors.
It was purposely meant to abstract the source, but yes, I'm generally referring to public funding (and certainly for the near and mid-term).
Once Starship is flying and a large space telescope can be designed to optimize the enormous Starship payload capacity and volume, the cost of the telescope should be able to be reduced significantly. Combined with dramatically reduced cost to orbit, the amount of money NASA will be requesting from Congress will drop by an order of magnitude or more, I suspect.
Unfortunately not anytime soon, and no way space science drops by anywhere close to order of magnitude...
probably ever. We're barely seeing an order of magnitude with Starlink vs incumbents, and that's the pointy end singularity that is SpaceX creating a very-for-profit solution. Other thoughts:
--Optics costs are unfavorably proportional to increasing size (as opposed to, say, comms payloads which are favorably proportional). Thats why, as you note above, aggregating smaller gizmos is ultimately a better path than building bigger gizmos.
--The Man simply doesn't have the capacity to figure out how to appropriately develop and fund a science program in a way that materially challenges the very established financial history. Any such undertaking needs an uncommonly disruptive visionary AND a space that provides material value when disrupted. Such a person will basically never exist in public office, and science is way down on prime targets for disruption...
--There are very few entities that can actually invent and build something to the exacting standards required for such a science gizmo--they have all the leverage and zero incentive to do any major favors on future builds. Why sell A Better Thing at half the price (on a years or decades more expensive dollar, no less) when The Worse Thing you sold last time brought in twice as many bags of money? And...we need to remember that science infrastructure is very much NOT analogous to Starlink, where SpaceX mostly just leveraged existing technology and established production concepts in an industry where the incumbents have been historically reluctant to consider terrestrial tech and prod.
--Honestly, launch cost is a red herring. As I've been saying for years here regarding F9 (and as history of the last few years has shown), its really not a major factor driving the payload side of the industry. This can't be overstated: In the space industry, SpaceX is all but a singularity regarding core philosophy and approach to creating solutions. Not unlike the auto industry vs Tesla, everyone else is
at best lagging by years or even a decade. Anything at the public funded level is even worse.