If you take a close look at the map design, youll see that all spaces are open, even indoors. This avoids camping and conservative gameplay (also realistic one)
I dont think going back to ww2 means that they make a shitty game, but yes, I agree that futuristic is tiresome. What they have to do is to change the game completely, latest CoDs are just run and gun games, the newer -> the faster paced action
I see that problem everytime there are sales in Red Orchestra 2, noobs get into the game and try to play it as if it were CoD thinking they can achieve easy and quick kills, but they find the reality of war: a well entrenched enemy that wont move much and wont expose itself much to your bullets
So, when you are able to achieve many kills with fast paced action, makes you want to keep playing and suceeding. Once you move to a more hostile and patient environment, you lose since you are not used to it
WaW was great: good map design, a good bunch of maps, free dlcs (map packs), own hosted dedicated servers, extensive modding support, zombie mode was something innovative and well done, weapons felt realistic, the game was immersive