Ah, the trouble with Hubble. I doubt Congress will fund any fix as they believe the James Webb Space Telescope will be the bright new shiny space thing. It is certainly generally superior to the Hubble. But here’s the thing, JWST is a bird in the bush and not in the hand. What if the comparatively much higher risk JWST mission fails?
Unlike Hubble, JWST will not be placed in the comparatively simple low Earth orbit. Instead, it will be sent over 3,000 times further into space to an Earth-Sun Lagrange point nearly 1 million miles from Earth. It’s helpful to remember the Hubble originally “failed” and required a follow up mission to fix its near sighted optics. That was comparatively simple with the Hubble just 300 miles away. With JWST nearly a million miles away, if something goes wrong it is unlikely a manned mission to reach it and fix it is possible.
The Hubble is our space bird in the hand and we should plan to keep it there.