No they haven't learned. I seriously think they believe the game doesn't have the following it clearly does. Why are they surprised at so many people? At so many people TRYING TO DO CONTENT?! WHY? You hype us up for an expansion you better believe there are going to be lots and lots of players! Blizzard learned their lesson after the failure that was Warlords of Draenor. Yoshi even said he liked Legion, so hence that means he at least follows what's going on with them. So he should know then the consequences of hyping players up.

Now we're going to go through the same tired motions of before. We get mad at the Early Access/Launch. Then we manage to finally play, get mad at things that probably should have been beta tested and then end up playing anyways.