If you only gonna go on the numbers then yeah sure but defender's true value is in the support skills it brings to the table.
WHIRLWIND
SHIELD PUSH
SHIELD BURDEN (gets resisted oooooooooof)
20 something second root from lvl 115 skill but that one I dont think can be resisted.
A shelter that keeps your obli up (unless you get pushed around by a skilled defender or death called by an avenger)
A good defender sets up kills by pushing people away from their party and overall disrupting the flow of things. Warlocks fit in the same category but YMMV.