The excuse last year for Ghosts probably resulting in lower numbers (which later turned out to be exactly what happened) was that XB1 and PS4 had near none existent user bases. Today you have roughly 15 million next gen owners in addition to the PS3 and 360 crowd
So to blame it on any console(s) is just a piss poor excuse. The reality is that in entertainment, everything has its heyday and eventually comes down. The new WoW expansion could ship with a cloned Scarlett Johanson and the subs would not go back to WotlK levels. Its prime is up, same with CoD
In my anecdotal experience none of the usual suspects have asked me about Advanced Warfare, none of my friends. They are mostly playing Destiny, FIFA and League of Legends these days.
Back during MW2 to about Black Ops 2, CoD was the talk of the town, it just does not seem that way anymore, anecdotally and according to Ghosts numbers.
(and i like the games, this is not a "haha finally bitches!" sort of schadenfreude moment for me)