Its all about playing smartly and not dumbly running into close quarter fights without a proper weapon. Its about playing the strengths of your weapon setup and avoiding the weaknesses. If you are using shotgun then of course you will have the upper hand in close quarter fights, its to be expected, of course you will be killed if you run with a shotgun out in the open. So its up to you to go with a weapon setup that'sgood all around or to focus in long range fights or close quarter fights and to play your strengths smartly. You can't complain shotguns are op when you run inside a building knowing full well an enemy is waiting inside in the corner waiting for you with a shotty, and you enter with a pulse or scount, thats just dumb