It is. Most older games have a life-time and rarely will see it return to the hights it used to have. Building further upon older games can keep you going, but if you want to be the new "big thing", which all the corporates want these days. WoW has had its glory days and unless we get something close to a remaster, it will not see those days again.
So yeah, using a number of years to build a new IP would properly be more profitable in the end, if ofcourse the game does not go the way of Anthem.
And yes, they have clear intended game design, but it sucks..... It really does. Its like the game version of Big Bang Theory, just boring and slow yet reliable.
I just know that it is really hard to change game design philosophy mid-game, so it would be really nice if they left something behind and just created a new IP with a better concept.