The cost of JWST is way out of control. You could build 10 space telescopes for less if you actually cared about efficiency and didn't need everything to be perfect for the first and only launch. Especially since the crazy folding mechanism would be completely unnecessary if you just launched them on Starship, which is big enough to hold JWST's mirror unfolded and possibly even the sunshade.
If you built 10 space telescopes for the price of JWST, I believe that EACH one would still be more expensive than the most expensive terrestrial telescope ever
I was only thinking of telescopes that currently exist, since it's hard to determine the cost of something before it's built. Inflation and such tends to make a direct comparison a bit trickier— it's not fair to compare JWST dollars spent in 2000 with dollars that won't be spent until 2025. Plus, even though these sorts of things typically end up being more expensive than the original budget, I'm being optimistic :)
I'm not sure switching launch vehicles is a realistic option for a project being in development for 24 years by now. Especially not to a not-yet-existing rocket.
