Originally Posted by NEOWatcher

Not being an expert...

I'm sure there are many similarities between them, since some of the functions and problems are virtually the same.
But; the Hubble goes beyond this because it is not a single purpose scope. Even if it were not built with servicability in mind, there is still a lot more instrumentation for a wider range observations.

Nova also mentioned that the mirror was the largest one ever in space. I doubt that something of this nature scales up in a linear fashion. So, even if the design were the same but bigger, the cost would be vastly larger.

"Based on" is a tricky phrase. It can imply both structure and concept, and can imply various levels of "sameness".

On thing that Nova made a point in thier introduction was the public outcry made in opposition of a Hubble retirement. (they said I think) Never was there such a public reaction to a space mission. Yes; other missions may have been historically bigger and more in the news and the public eye, but they didn't invoke this type of reaction.
So; this caused some re-thinking of ways to save it that weren't in it's design.