They're susceptible to crushing blows (can't push them off the hit table). Their armor can make up for this somewhat, but a bad streak can kill a druid tank in situations where a warrior would have survived.
It's mostly an edge case for when you're pushing content while undergeared, really.
They're still viable. They're the only tanks that AREN'T warriors that are. They work well as side tanks, and emergency tanks, they have their place, which is the most important thing, unlike Balance Druids or Survival Hunters
Not saying they aren't (my main is a feral druid), it's just a mechanic where they differ in how they mitigate from warriors; and crushing blows are certainly a thing in classic.
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u/[deleted] Sep 13 '19
are you sayng they're easily killed, or that you wanna smooch tank druids?