So how can a great system solve less than great recordings


It seems no matter how good a system is, the quality of recording quality takes priority.

Formsome reason nobody talks about challenges of making older recordings sound better.  Classics from 70s and 80s are amazing tunes, but even remastered editions still cant make sound qualiity shortcomings all better.  Profoundly sad.  Some older stuff sounds quite good but lots of stuff is disturbing.


jumia
You're over-generalizing. At this level of analysis anyone can say Edison made lousy recordings on his wire thingy, the gramophone sucks, how can even the best system get fidelity from tin cans and string? Fraid you're gonna have to up your game a little to have something more to talk about.
You pay your money. You take your chances! Considering the problems of capturing sounds with a mike it is a wonder that there are so many good - and better - sounding recordings available!
If you’re interested in classical and jazz then you should see the remastered reissues from Pristine Classical. They take albums from the 20s to the 60s and make them absolutely amazing with their XR filtering.  You can’t almost tell the difference between a a recording on the 30s and 60s. 
Their recent Miles Davis reissues are sublime. 
You can also stream from their website.