>>149045422
Easy:
>End show on a cliffhanger that many people found hard to enjoy
>Seven years of hiatus, throughout which world as a whole has fundamentally changed and not for the better, people moved on to other fandoms, tastes in media changed as well
>New season has been teased every now and then, but offered nothing to fuel speculations and anticipation
>New season is finally coming out and it's just more of the same
Or to put it simply, Ben was dragging his feet for way too long and most of the original audience had moved on.