See also SpaceX vs. NASA. No way would NASA have been allowed to blow up as many rockets as SpaceX did to finally get to their working solution.
The same people when SpaceX blows up a bunch of rockets: "wow, look at the innovation, they move so fast! Cut NASA funding and give public funds to the guy who purchases elections!"
The last time NASA caught any serious flak was what, the Starliner shitshow? And that was just splash damage from Boeing getting dunked on by everyone at once.
I'm not sure what timeline you're thinking about, but JWST was launched pretty recently and it's pretty ambitious. But more to the point of my earlier post, NASA's "lack of ambition" is probably directly attributable to the "small government" people who penalize ambition in the public sector and praise it in the private, government contractor sector. The incentives to be ambitious in government are perverse when every "failure" is scrutinized and condemned by people who want government to fail so that they can justify taking public money and dumping it into private bank accounts.
Milspec is expensive and process heavy, see what a B52 replacement trash can costs, for just one example.