I, sadly, never used hearing protection because I was singing as well, and any sort of ear plugs made it hard for me to sing. I spent from some time in the mid-80s to the late 90s blowing my ears out, including a run from '94-97 where I was using my JCM900/Carvin 412 stack 4-5 hours a day 5-6 days a week.
While I don't have the traditional concept of hearing loss, I do have this weird affliction I refer to as loss of hearing depth perception. If I'm in a crowded room with a lot of people talking at once, I have a really hard time differentiating between the person speaking right in front of me and someone who's talking on the other side of the room.
And, just to clarify, the spirit of the opening post wasn't to advocate for self-inflicted hearing damage, but more to endorse every rock/metal guitar player to jam through a full stack blasting at 100DB+ at least once in their life so they can fully experience it. This sort of music is more than just an audio thing, it's a feeling as well - people "feel" the bass, feel the wall of sound impacting the entire body, etc. And, with Rock & Roll and Metal intended to be played LOUD, it's hard to believe someone who has never performed anything above "bedroom player" volume truly appreciates what they're trying to create/re-create.