It would be really overpowered. Stealth is quite strong in a game where everyone else is visible on the minimap as soon as they start shooting.
This isn't meant to be a realistic game. Why do bullets curve out of your gun at impossible angles because your sights aren't lined up? How do your wounds automatically regenerate? Why do you have a crosshair overlayed on your vision? Why can you guide a missile from beyond the grave? How do you pick up weapons without touching them? How do you pull all these drones out of your a**? When you reload, how do all the bullets in your current mag get transferred to your ammo pool such that you keep pulling out full mags instead of cycling through used ones? How can you throw grenades more accurately than you can fire a gun from the hip?
Realism isn't a very good argument for ignoring balance in a game riddled with unrealistic mechanics that place gameplay first.
Not ignoring balance, but addressing it. Guess you didn't read well enough. It's all about the degree of realism you want to look at. You regenerate, but you still die when getting shot at. I can't believe you used the cross hair as an argument. It doesn't take that many wits to realize that you do pick up weapons with your hands, it's just not shown because animations weren't made for it. Even the argument about grenades and hip fire seems like discharging rage for not being able to fire correctly in game. ( Yes some people happen to have insane accuracy throwing objects while maybe not being able to have great one with a gun that has recoil and spreadfire.)
Taking the suggestion out of context and trying to explain it with unrelated examples, exaggerating the degree of the suggestion isn't a very good argument. Might want to read this time and look at the things that could be done to make it balanced, while reflecting the actual purpose of the silencer. Your arguments are as good as me saying: ''This is a game, allow my shotgun to shoot rockets because it's overpowered how I can 1-2 shot someone at close range''.
The adjustment suggested is just so it reflects the use and behavior, not realism. It just happens a few ignorant people in the post have stuck to the word and it carried on as a snowball effect. Notice how it has been said that to use such an attachment, realistically you'd need a special type of ammo. Did I ask for it ? No. Because it would be useless, the ammo type that needs to be used can be assumed.