Aging ears and Nuances

I am 77 years old.  I can't hear like I used to be able to, but like you, I can still hear some things.  My hearing extends out to 12-13 kHz, it varies a bit day to day.  In fact there is precious little music above 10 kHz, or even less.  It is really more a question of how disciplined you are in how you listen.

I’m 72,  I hear soundstage and instruments texture just fine. I gave up on listening to small differences in components years ago. It became completely unnecessary to enjoying the music. The advent of streaming has been  one my many joys in retirement. 
Rich

I am 73 and have found no reduction in my ability to characterize and discern nuances in high end systems. Overly trebly, hard and distorted high frequency bother me as much as ever.  

All the nuances of the midrange are still there. I know my high frequency hearing is not as good as it used to be, but my experience listening seems to have made up for it. When I listen with younger folks, our observations are the same as we compare notes. Also, high frequencies affect lower frequencies, so if you get them wrong the overall sound is negatively affected. 

I also get to listen to different systems... some of lower quality and some of higher quality... and of different character. The differences are instantly obvious. 

I believe all of you. However, one sign of agedness among some of the faithful gathered hereabouts manifests in our tendency to repeatedly hash over old arguments like a bunch of old duffers sitting around the pickle barrel in the general store. Wouldn't have it any other way. Sometimes if an old argument is sampled daily for centuries it can turn into something magnificent to behold - something entirely unexpected.

According to the VA I have lost a bit at both ends of the spectrum. Nothing too bad. 
My problem is not what I cannot hear. It is what I do hear. 
All that said being in my 70’s with a myriad of issues I had to downsize to equipment I can physically handle. Moving around 100 pound amps and speakers is simply no longer an option. 
A word of advice… please do not ever tear your quad tendon off the bone.