I have been playing since Vanilla open beta and I have never seen such a drastic drop in player participation so early in an expansion.
I can put up with a lot of bad game design. I can almost always find something to do. However, this time I am doing things in game more and more by myself. I have a decent amount of players on my friends list. And each week more and more friends stop logging in due to boredom/bad game design but mainly because their guilds are dying.
It is hard enough to find four other geared/decent/mature players to do M+ with, and getting near impossible to have twenty on to do M Uldir.