Title says it all. The Gameplay element doesn't matter- every race should not be able to be every class. Yes the Lore is already messed up with timelines and what not, but allowing every race to be every class is just too far.
An Orc paladin would not make any sense what-so-ever. It would not feel right, nor should it. While I will admit some of the race/class combos were pushing the limits (Worgen Druids with the Harvest Witches...) Just saying "fuck it" and abandoning all lore for gameplay just isn't right for the game,