I saw this on Youtube and it really is, in my opinion, something which would be an excellent addition to "Return to Castle Wolfenstein - Singleplayer" gameplay. The availability of iron sights :

Please. Do the opposite; keep that away for shooters having real use of. If RTCW lacks iron sights, it is for big reason.

But what will be a purpose of it? I do not get it fully.

Many players prefer using iron sights in-game, Zenci, because it helps to improve their aim.