There's a ton of compromises like this in video games. Like "shotgun=short range damage" or the ability for players to alter their trajectory mid-air. Similar changes are often made in the name of atmosphere.
Everyone does it the 'wrong' way, and we end up with a bunch of ignorant people who don't understand that a flag on a sailing boat indicates apparent wind [0].
It's all very well to claim 'atmosphere', but shit like this ruins the atmosphere for people who notice the details.
Shotguns being the way they are is less about sticking to what people believe to be true and more about making them feel significantly different to other types of fire arm. If you were to have a shotgun with a realistic spread in most games the gameplay would suffer.
It is a tough choice! See also foley work for nature documentaries. I don't even think it's ignorance so much as intuition - even if mistaken - is a central component of aesthetics. There's an expectation that it should sound like this, it should blow that way, etc.
