Okay, @TIREUR This is a lot of work gone into a topic but...
I'll have to argue against you.
I'm not going to cover everything so I'll be glad to reply again.
@Viritrilbia pointed out many things. So...
First off, all weapons have their roles most of which are not well used.
Such as LMGs, they are the King of destroying snipers.
They're suppression is enough to stop any sniper without a professional level of skill.
All this is based on skill wise, if a argument is going to be based on this then it will be counteracted by the same argument.
Second, snipers are meant for long range as stated but how well do they perform close up?
Most people bringing a sniper into CQC will die almost instantly with the occasional lucky shot.
Third & most notably, THE SKILL CAP.
Snipers are the guns that arguably need the most skill in the entire game to use.
There's a reason you don't see many snipers, especially good ones.
And that reason is the amount of skill required for it.
Sniping requires the most utter precision, & very fast reaction speed for CQC.
You miss one shot, & any person playing the game for a while will take cover or shoot back.
You'll have to wait till the round gets loaded.
One, argument you had was about how anyone can compensate for bullet drop.
That's utterly incorrect. Most snipers can't compensate for bullet drop or do it in a timely fashion.
I could go on, but I'm tired. If you do rebuttal to this then, as I said, I will reply back.