I'm also 68 and my hearing is about average for someone my age. I recently played a test CD and I can still hear 12K Hz but that's about it. I went to many loud concerts in my youth but I learned early that earplugs make the experience much more pleasant. I smoked in those days and tearing off the filters from a couple of cigarettes and stuffing them in my ears worked reasonably well. Later I discovered Etymotic earplugs and wore the religiously at loud events..
To answer your question - no, my high frequency hearing loss has not led to any changes in my system. I will readily admit that I can't hear the subtle differences that other audiophiles seem to hear but that has always been true. I can't hear the difference between interconnects but I couldn't hear the difference 30 years ago either. I've got several DACs, two transports, and a couple of players ranging in price from $800 to $20,000 and they sound extremely similar. I couldn't guarantee that I could tell them apart in a blind test. But I've been to three audio shows and I can certainly tell you that I can distinguish between mediocre systems and very good ones. I also discovered that my system holds its own against most of the six figure systems I've heard even though my speakers, amp, and preamp, are late 90's vintage.
I had an interesting experience in the Synergistic room at AXPONA in 2018. They had a very nice setup with big Magico speakers and they did 3 before/after tests. For the little HFT thingies I couldn't hear any difference but I would say that most people in the room felt they could hear the effect. I talked to several other people who were younger than me who couldn't hear the effect either so I don't think age was a determining factor. But when Ted turned off the Atmosphere gizmo the difference was astounding (at least to me). The soundstage collapsed from 3 dimensions to a flat wall of sound. I was absolutely blown away but some of the others in the room went, "meh." What I drew from this is that I am probably very sensitive to soundstage issues but maybe not so much on frequency response.
One more note about how we process sound quality. At the same AXPONA they had a room with very large Wilson speakers and D'Agostino electronics. This system sounded terrible to me. It had an etched character in the high freqencies that made it sound more like a lab instrument than a stereo system. I talked to several people about this and reactions ranged from, "I couldn't stand to listen to an entire song on that system," to "Best sound at the show. Incredible." Age didn't seem to be a factor with the people I talked to in whether or not you liked this sound of this system.