Is Warrior the weakest of the tanks?

[Shinkyo]

Hmm i play all three tanks and i find warrior the most squishy of them all, and when Im healing they seem pretty squishy

There's absolutely nothing in the class design that makes them more squishy aside from the perception that they take more damage due to how their tank stance work.
They might feel squishy because their HP drops more but they don't require more healing than other tanks.