I feel like what they come up with as a main plot and final objective for an entire two-year expansion (assuming this is the model they continue to use) must be such a fine line to walk.
For instance, if looked at, say, Wrath, which was such a success, and tried to just recreate it, beat for beat (big baddie must be stopped, takes us a long time to push all the way to his front door, must train to be ready to fight, and finally rade his palace), we’d get bored and say they’re being repetitive.
When we go another direction, such as BFA where there is no ultimate big baddie, just an evolving story, bringing us to new areas and fighting different foes (Aszhara, N’zoth), we feel like its too out of the blue and too rushed.
When the big baddie comes from nowehere (Jailer) we feel uninvested and uninterested. When a popular lore character devolves into the new baddie (Sylavanas) we feel they did her wrong.
A lot of this is probably in the execution, and you’ll hear no argument from me about how they have fallen short a lot over the last few years. I’m just saying I wouldn’t want to be in their shoes. They will never please everyone, that’s just impossible.
Very few I have seen, including on these forums, have come up with actual expansion concepts I would say sounded genius. Otherwise, I think most of us (myself very much included) probably couldn’t do much better at, once again, planning the story beats of an expansion that aims to keep players invested for 2 years.