I have never seen a game that take into account the sheer pain and disorientation from firing a firearm indoors without hearing protection.
While running down the narrow halls of an underground vault with metal walls, my character fires off hundreds of rifle rounds into enemies.... I recently paused to imagine just how horrible that would be. Firing rifles inside a vault without any hearing protection would almost guarantee ruptured eardrums, bleeding from the ears, extreme disorientation, and ringing of the ears that could last for days. In any indoor setting, discharging a firearm without hearing protection feels like getting your ears boxed at a minimum. In a metal vault, firing a rifle would feel like getting flash banged.
Even beyond the inevitable permanent hearing loss and hours of disorienting tinnitus, there would also be a psychological aspect to keep in mind. After firing that first shot and feeling like you got svcker punched in both ears, you will become hesitant to take any more indoor shots in the future. It is the same concept as subconsciously developing a flinch from firing lightweight magnum rifles with killer recoil. (keep in mind that if you have shot a firearm at an indoor range, they have sound dampening walls to help minimize these effects..... and it is still extremely loud)
Just firing a little AR-15 from a porch that was enclosed on 3 sides without ear protection was really uncomfortable for me and made my ears ring for hours. You couldn't pay me to try firing it from inside a closed shed without hearing protection.
Keeping this in mind could greatly increase the the usefulness of melee weapons in games. Plus, electronic noise canceling headphones still let you hear normal sounds like talking. It just seems like the shell shock concept is lost upon games.