I'm sorry did you say MoP was awful and admit to never playing it? I don't get this mentality of people being unable to make a self informed decision, My friend said it sucked so by extension it must suck. ...how about making an informed decision at some point, by.. shocking... TRYING IT!!!
Ideally no one has ever hit the level cap of the last expansion, looked at their dungeon blues, and thought "I win."
And "lore-relevant" is based on the user's opinion, which mean you're opinion does not equal theirs.
But you could be right, that challenging content might not be enough. People might have quit for that. Some people could think the game is getting worse and quit. But will we know for sure? It's something impossible to know or pinpoint.
Anyone who says they know the main reason for sub losses and that reason is the thing they didn't like is just making themselves look ignorant because no one here is silly enough or brainless enough to fall for it.
The trick of selling a PvP-MMO is creating the illusion among gankers that they are respectable fighters while protecting them from respectable fights, as their less skilled half would be massacred and quit instead of “HTFU” as they claim.