Despite the slight change in the curvature of the main mirror, Hubble's images were pretty amazing
Amazing maybe, but far below what was promised. There isn't any way to gloss over the fact that the project managed to screw up the single most important component in the telescope. The mirror ended flawed and in orbit not because it was too technically challenging, but because of arrogance, sloppiness, and poor oversight. The taxpayers have a right - even today - to be pretty steamed about it.
Imagine if someone sold you a sportscar, promising it would handle like a dream and hit 200 mph on the straightaway. When you finally receive it and test it out, it shimmies like a banshee and can only manage 100 mph. When you call to complain about it, you find out that during construction, the technicians got drunk one night, ground the cam shaft wrong, and left out one piston. The company sold it to you anyway, not because they were trying to cover anything up, but that they simply didn't know anything was wrong, because they'd never bothered to test drive it before shipping it. Your argument is that we should still have been happy to have it because it's better than the Honda Civic we were used to driving.
And, given the etymology of the word , "disaster" is a good choice.