Yeh I see ur point but for me that's not a problem because I choose classes for their gameplay, lore and flavour. I think that would be a problem if we could only have one class per server or smthing like that. If Blizz wanted us to play only one class, then druids being able to do 4 completely different roles would be an issue for sure. But we can have 11 different classes per server which means players should have alts so you can be a rogue dps and a druid as well if you like their tank spec. And even if you still feel like druids have the winning edge on lfr or lfd because of their multiple roles, I think you need to consider that just because a druid can change specs to become a tank doesn't mean it would be up for the task because he would lack the equipment.