I find it funny how just because some people haven't liked games like Oblivion and Skyrim as much as previous titles, they're convinced that the series is in a decline and will soon die. And yet, Skyrim is by far the most popular Elder Scrolls title ever.
I'm going to give the obligatory example of Call of Duty here...
Call of Duty is HUGELY popular.
However, one cannot argue the fact that it is also one of the most hated franchises at the moment. This "popularity" you speak of consists of nothing more than mindless drones(players) that have no idea what they're playing nor what they could play.