Van Halen and Rush were the loudest I heard, both playing Madison Square Garden for the first time early 80s. The Who at Shea Stadium were loud but it's outside and they had other crowd problems far worse.
Had tickets in the first five rows to the stage for both Van Halen and Rush. A guy behind me at the Van Halen show were chatting randomly before the show. Into the second song, I turned to him and he was tapping his ears how loud it was. He was clearly overwhelmed by the volume.
My friends who were in high school played music and worked on 48th St. Music Row in NYC. They all brought Sonic II earplugs which cut high frequencies. I had a pair of course as I learned from these guys to be careful at the young age of 17.
Recall pulling the plugs out during the show to check how it was and being overwhelmed the loudness. It had to be well into triple digit decibels, over 110 db.
After that July Van Hallen concert, everyone marveled what a great concert it was. Everyone was blown away from the opening number "Fire." But at least among our small group, no one suffered any negative hearing impact. Everyone kept those Sonic II earplugs in and today, even though on occasion I like to play music on the louder side, no hearing loss other than the typical high frequency reduction due to age. I can't even notice that either and think my hearing is good to go.
Sorry to hear of the trouble so many have had. I hope there is some new treatment to aid tinnitus.