For those who love Classic, bfa already IS dead.
But I believe there will still be a large number; a majority of mainstream tablet gamers who have been spoiled too far by instant gratification and participation rewards. They are conditioned to led-by-the-hand tutorial/quest assistance and frequent strokes of the variable reward system. …and they don’t want to need to talk to others and group up to get completes.
The heavy social element, the time investment, the talent tree, no transmog, personal stake in your character,…these and so many more things that make those who love Vanilla, love it…these things will confound the 60 character tweet mentality of the mainstream gamer. They’ll be disenchanted as soon as they realize they have to put in time and effort and they’ll leave.
That’s just my opinion.