Apropos hearing loss, mine is age-related, not due to damage. I don’t go much beyond 12khz, which is normal for a male approaching 70 years. This does not affect my hearing or judgement of the midrange, which is where most of the critical musical information resides. I’d say my judgement of what sounds "real" to me is as good as ever. Maybe I’m missing some high frequency harmonics on cymbals or whatever, but it doesn’t detract from my enjoyment. The system is tuned to my taste based on all the factors I mentioned, including tube choice. Switching out a rectifier tube can make a difference. I can still hear little differences in tone. The system is not "analytical" or "bright" sounding- to the contrary, it is a little on the warm side without sounding euphonic (to these ears).
PS: where I have difficulty is in public environments, like a noisy restaurant with high ambient noise- where I can't even hear a dinner companion to hold a normal discussion. This has little bearing on the hi-fi, where the ambient noise of the room is relatively low.