I'm well aware of the capabilities SpaceX is promising! This is why I said, "even if the telescope was teleported into orbit." If a new ground-based telescope is still $1 bil then something which has to operate in hard vacuum, high radiation, and with even greater temperature differences, with far less provision for repair (even with Starship), will be hard-pressed to come in at an even smaller budget. Then again, $1 bil ain't what it used to be.
On the other hand, you don’t need a massive, expensive structure to keep the mirror from deforming under gravity, everything is already vacuum insulated for you, humidity isn’t a problem, you get 24/7 energy from the Sun using just solar panels (no diesel generators), you don’t have concerns for building on sacred land, you have like 3-4 times the observing time per day (which directly impacts cost per observing hour), independent of weather, access to both hemispheres, and no (or much less) need for expensive adaptive optics and laser systems to partially correct for the atmosphere.
All true! And mostly better for the ultimate purpose of a telescope, which is why we prefer to put them in space. However none of those advantages offset the greater cost, e.g. your "expensive structure to keep the mirror from deforming under gravity" is simply a steel scaffolding. Admittedly to higher precision than an office building, but not extraordinarily so. I think perhaps you are not respecting the challenges of space and the cost to operate reliably in it, even if launch costs were zero and mass unlimited, so I'd encourage you do do a little more research.
