I know one thing they've totally lost. Community interaction.
They used to make posts all the time asking players what they thought of new tier sets, new raids, new dungeons. The last time I saw a post even resembling that kind of interaction was around patch 4.1
They seem to have totally forgotten that we are the consumer, not them, and we are the ones who decide what a good feature or bad feature is, not them.
Today they just defend bad choices that the community at large hate. Legiondaries, defended to the death. Titanforging, defended to the death. They never stopped to think "Hmm, if 90% of our community really hates a certain part of the game, maybe we should remove it." Instead, they defended their bad choices, and pissed a lot of people off.