@rankaudio If your friend has been subjected to a lot of loud noise all their life, and has some serious loss of sound, then maybe, but loss of upper frequencies and nuances, um, maybe he's just tired of dealing with equipment, or was not as hardcore an audiophile as you thought. Or, perhaps other things in his life may take precedence over stereo equipment. I could see that.
Aging ears and Nuances
I spoke to and older audio buddy of mine and he made a full 180 on his nice tube gear and just went with lower cost streamer that can also be used as a preamp. He says he doesn’t hear much above 11.5k. My tests let me hear up to about 13.5k but I’m able to hear even subtle differences between tube amps etc quite easily even though most of the music is in lower frequencies of the spectrum regardless. Does anyone here find themselves experiencing a more difficult time appreciating the nuances with their age? And has it affected the choices you have made with gear, not being as picky?