I'm pretty sure if MMO's looked like this,a lot of people would come back. I know the MMO generation grew up and time and families took over but I'm pretty sure one of the other factors is the mmo cartoon fatigue.
For me, good job, great wife, kids are grown. I have the spare time again, I just don't want to play a nearly 20 year old cartoon. I get Nostalgic play but that's temporary. Give me modern day Unreal engine MMO. EverQuest, WoW... Make a Diablo MMO or some shit. Just make it look like this.