imo, yes, if games want to harp on realism so bad, then make the Sniper Rifles one-hit kills like they are in real-life.
But, by that same logic, MAKE THE SNIPER RIFLES ONLY EFFECTIVE AT FAR RANGE. Stuff like quick-scoping, no-scoping, and whatnot takes skill, I'm sure, but it defeats the entire purpose OF a sniper rifle. If you're going to make a realistic sniper rifle, MAKE a realistic sniper rifle, where the thing is hard to carry, takes a while to set up, and you sure as hell can't immediately point it at something charging at you from the side and reliably hit it.
If they refuse to do that, then yes, do not make the body-shot a one-hit-kill. I respect no-scoping and quick-scoping and all that stuff, but at the same time, I find it stupid to do all this stuff to the sniper rifle that makes it far less effective to use it as its actual purpose (you know, sniping).