Loud movies

Okay so I just saw Dune part 2 in IMAX - admittedly a bit late to the game. But I was shocked by how damn loud it was! I literally pulled out my SPL meter app for a 5 min stretch and measured 103dB multiple times and it was pretty consistently 90ish. Granted, this was during a particularly loud part and I know the subs in the theater were working hard but still. Is this just because it was IMAX?

Also, I know I am well on my way to being a grumpy old man.