[avmich]

This is, of course, a stretch - requires to have a really good relationships between USA and Russia.

But technically, bringing Hubble to the Shuttle cargo bay doesn't change things much. Ok, the telescope isn't flying anywhere - but if you have a Soyuz nearby, you could also attach it to Hubble firmly enough, just as with Shuttle. And just as with Shuttle you can't avoid having to work with the instrument in spacesuits - since you can't bring Hubble into the pressurized environment where the spacesuits are not needed.

So, I don't know for sure how many technical details should be overcome for that mission to work - but in principle you at least can get to the Hubble with something different than the Shuttle. Today it could be the Crew Dragon, and 10 years ago it could be Soyuz.