So much wrong with this post I don't even know where to begin.
First, if it is in the game, then it is in the game. It has stayed that way over many years because it is actually balanced, or so have thought the majority of the players before you. If your opinion differs, then maybe it is time to ask yourself why it has stayed that way.
Second, players who use autosnipers can (and should) get their ass handed to them on a plate by any decent player with an AK/M4. There is a reason this weapon is seldom used in competitive play. However, on pub and on D2, it is the only weapon that can save B when you are alone defending the rush.
Third: P90. Pathetic weapon at long range. Understand that it is entirely your fault if you don't prevent the opposite player to get close enough to spray-kill the shit out of you. I get so many kills rushing on D2 straight up the middle with P90 (often round after round after round), because noobs don't pay attention, don't counterflash, etc. And then they cry about the weapon instead of doing something about their idiotic gameplay. Just stop me before I pop up in your face, it is actually easy. I can't pull this shit when regulars are on, because they do the simple things that protect them from my P90. Just LEARN instead of crying.
Fourth: the "whole team dead" comment... This is only true when the players are stupid enough to stay in front of the goddam autosniper, and unfortunately this happens a lot on Setti. Just learn to use smoke, flashes, and pay attention to how/where/who in your team gets killed. I can't understand why a whole team would go, one after the other, without smoke or any decoy, one-on-one with an autosniper or an AWP. But these days, they do. And then they cry...
It is so much easier to blame the game than to actually try to get better at it.
So, we will have to restrict the autonoobs? the P90s? the AWPs? Maybe you also want the AK restricted while we are at it? After all, it is so much easier to cripple other people's ability than to improve yours...