The gigs i have seen at Wenmbley Stadium were not loud enough, in fact a lot of UK shows that i have been to over the years were not loud enough for me.
Weird thing was the support bands were louder , plus the records being played before the show. I guess England is one of those places with over the top curfews in place.

A thing i do to help with this problem is i wear ear plugs at the gigs until the Stones come on , then i take them off and "Ta da", the Stones sound loud enough.
I don't want the support acts to blow my ears before the real deal begin to play.

The John Entwistle Band, playing in a small club in Detroit in 1998, was the loudest thing I've ever experienced. I stood directly in front of him, no more than 8 feet from his massive bass rig. My ears rang for 72 hours. Here's a sample:

[www.youtube.com]

Led Zeppelin in Liverpool March 1971 was so loud (and I was standing at a reasonable distance) that it hurt. I left halfway that concert because of that but, although they played well, also because they were very boring.
I can't remember exactly, but several decades ago I saw Jetro Tull in "de Doelen" in Rotterdam NL and my only functioning precious ear (since birth) kept ringing for three days. Ever since I always take small cotton wool plugs along. The Stones concerts are in general fine in terms of loudness, but occasionally (like Dusseldorf 2014) in indoor stadiums I filter some noise with a plug.
Like BV says, once destroyed, there is no way back.
My neighbour, who works for an institute dealing with deafness problems, said to me on several occasions when a car was passing by with blasting (music or "bang-bang") noise coming out: "Ah, here goes another future customer". Sinical, but oh so true

I've seen the Stones 3 times: the first was STEEL WHEELS in the Silverdome outside of Detroit and it was perfectly loud. ABsolutely brilliant. The second time was in East Lansing, MI for VOODOO LOUNGE in Spartan Stadium, an outdoor college football stadium, and the sound was borderline OK, not LOUD but almost not loud enough.

The third time was in the Superdome in New Orleans for VOODOO LOUNGE and it was horrible. If it had been LOUD loud it would've been better considering only about 24,000 people showed up but it was so rumbly it didn't matter.

I've seen U2 twice, both in the Superdome, and THE JOSHUA TREE show in 2017 was absolutely magnificent sound wise.

I've seen The Cult a hand full of times in various size venues and all but one show were perfectly loud. I've seen loads of other bands in various size venues and, with exception to standing up by the stage, I don't think I've ever been to a show that was too loud.

just chuck