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 
If I wanted to use iron sights I'd play pavlov be
If I'm using a mous and keyboard, please let me bunny hop and hip fire like a cracked out demon