But for FPS games, realism is directly proportional to the hardcore level of the game

In the case of Armed Assault 3, there are a number of modules that are made to enhance the realism of the game in order to achieve a higher level of realism. Once you install these modules, you'll find that using a sniper rifle requires adjusting the closeness based on distance, and that it requires calculating wind and humidity based on a ballistic solver. I'm not sure how many players will use these game designs correctly, but I'm afraid it's hard enough just to understand the terminology