It isn't about making every gun the same. It is called balance. As long as every gun's ttk is around the same number than a game is mostly balanced. Of course true balance isn't possible but it is about getting as close as possible. Guns will still be fun to use but there will be more options. It will be fun to get killed by Suros, Hardlight, Monte Carlo and the various other guns that have fallen to the wayside. Shotguns didn't really need a nerf. It was the two perks Shot package and rangefinder that made them too effective.