I'm willing to say that most D&D players play MMO's.
I don't mind you (I hate fetch/kill 10 of quests), but pretty much everyone I know does.
Most people I game with have played MMOs and found them wanting.
Most people I game with have played MMOs, found them wanting, but still play them.
I like the online DDI tools and lack of online support would be a major hurdle for me to implement 5e.
But I don't understand people paying $17/m for a mmo subscription grumping about coming up with $5/m for a character builder, monster archive, virtual table, access to every rule ever printed, and every back issue of dragon/dungeon.
It just seems to be that so many people simply just don't like D&D and would be happier playing a different game, but instead they want D&D to become that other game.
Which then ironically, forces those that actually like D&D, to go to clones of past editions. And in this case, Pathfinder is doing well enough that it is taking significant market share away from D&D.