In terms of gameplay mechanics, old school zoom aiming achieves the same thing as ADS. Is getting to press your nose against virtual firearms really that important in a game about shooting werevolves and vampires?
I blame this on the proliferation of Call of Duty over traditional scifi and fantasy shooter franchises. You can fucking ADS on an assault rifle in Halo now 
Tarkov is much less realistic than it claims to be. It's as much of a mech game, with locational damage and armor, ammo types that have drastic effects on gameplay, weapons that all behave quite differently. In a game like, say, arma, all guns are basically the same because outside weight and ergo all modern rifles are basically the same. Ammo does matter, but it's more about how flat the trajcetory is. The game models armor but there are no magic bullets that can arbitrarily pierce rifle plates.