People are leaving WoW because they are done with it. See what happens when you make things more accessible? All those casual players that don't have time to play much, and therefore need LFR and LFG are leaving to go play other games. They will go back when the next expansion hits, burn through the content in 3 months and start leaving again.

Hopefully FFXIV won't make the same mistake of sacrificing fun and engaging gameplay for the sake of accessibility.