Certain genre are definitely been vanilla-ed. When I first started playing mmorpg's, there was a sense of accomplishment when doing a quest. A journey if you will , in the process of obtaining the quest goal. Ever since Blizzard has liquified down the mechanics to what an mmorpg is, mmo publishers time and time again wanted to copy the "WoW" like numbers.
Few games broke the WoW mold, and those games where met with punishable reviews, poor sales and in some cases actual world closings. Shadowbane , which was the pinnacle of PVP in an mmorpg was without a doubt one of the best games of ever produced, but because it failed long term to generate WoW figures, it shut down.
If we really look at the problem, it was not the actual games themselves that got dumb-ed down, but the reaction to what sells forcing developers to dumb down the games. As long as consumers continue to by easy mode game titles, the games will just get easier and easier.