I don’t actually know how they do it in movies but from this one example I’m assuming it was industry standard but I could be wrong.

Other movies might do what you said e.g. airsoft gun or fake gun, with edited sounds later

I do find it hard to believe the industry standard is to use real guns with blanks but it may be that way. It’s a lot simpler, but obviously more dangerous

And yes guns are very loud, after a gun goes off beside you, you will have a sort of numbing in your ear for a few seconds and you can’t hear anything out of it lol