Honestly, speaking from the perspective of a Gnome Warrior whose Escape Artist fails 80% of the time, I don't even think Druids are the problem. At the moment, PvE Rogues are the most powerful class in WoW by far. Druids, I think, are "meant" to be countered at high levels by Paladins. I think DPS/Paladin teams do pretty well versus DPS/Druid teams, mainly because JoJ + Hammer of Justice is often enough to kill a Druid.
Druids are fairly overpowered compared to other healers, but in relation to other DPS, numerous classes have pretty solid success against them. Warlocks can do heavy damage to every Druid Partner but a Rogue, Frost Mages can kite Warrior/Druid indefinitely (but not Rogues), Hunters destroy them, Priests nullify a lot of their effectiveness as both Shadow and Disc, Paladins can LOS/out mana/JoJ them, Shamans can Ground/Shock/Purge them, and such. But they all fall to Rogues

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I think the metagame has always been melee classes should fall prey to kiting. Warriors> Fear-dependent CC classes while falling prey to Kiting. Min-maxed Rogues were historically weak to kiting as well, while also being weak to fear. Now, of course, they're Undead with impunity against Frost Mage kiting. And their damage has scaled to the point where five seconds of alone time= 50% health or more. While my Warrior doesn't have as many problems peeling a Rogue (although even that is extremely hard, far harder than it should be with Vanish, Shadowstep, Sprint, and Deadly Throw/Blind/Trinket), my Mage often has to Ice Block within a few seconds. It goes Opener- eat, Kidney Shot Blink, Shadow Step and then I have to Ice Block or Opener- Blink, Shadowstep Kidney Shot- Trinket, and then that leaves me open to Blind or even the Rogue trinketing/Cloaking and getting within melee range. Then, any Sheep or hard cast I make is interrupted with Deadly Throw.
Rogues basically have no counter class and can destroy any armor type in one Kidney Shot. If that KS is trinketed, the Rogue can Blind the target, swap to partner, and have another Blind up within the minute and thirty seconds it takes for the other team to stabilize. This is without PvE gear, throw that in and it's seriously ridiculous.
Also, it's a shame that many top Holy Paladins have quit healing on their toons. Most Paladins, even in 5's, that I've seen are Ret now. And I think Paladins are one of the few classes that can actually counter Rogues decently, now that Warlocks are gone.
Warriors were overpowered but you could always blow up the bad ones and the good ones when RNGed from something like Blackout. But Rogues are immune to such blow-up tactics, have unlimited ways to ensure drinks for their partners, and when min-maxed can stop all weaknesses.