There is a lot of contention between casual and hardcore player base.... and how our rewards for gameplay should be implemented
Some people say they deserve better gear or better rewards, because they do different content they perceive as being more substantial. In reality though, everyone chooses the path of least resistance, we always choose the easy way.
That's why there is META for mythic dungeons... people want the classes that make the runs easier for them
That's why there is META in Arena... people people want the easiest chance to win
That's why there is class stacking, and guilds choose the OP dejour for Race to World First
In any RPG MMO, the player wants his/her character to feel stronger next week than it did last week.... no matter what content you choose to enjoy.
Blizzard needs to either balance it's classes with equal AOE and single target, or they need to come up with upgrade systems for every style of player, because no one wants to play an mmo and feel like their character is stagnating