Because they get a 3 sec god mode....that's it.
Let's check out marauders though:
Invis + dmg reduction
Cloak of pain
Let's keep comparing Ops vs marauders though and see who wins the OP challenge.
4-second non-channeled stun
Dedicated burst heals > 2% heal on a crit
3-sec God mode and burst heals to replenish all health
Out of combat 8 second mez
Cover mechanic for preventing Force Charge
AND top of this, I don't care about operatives. They are FINE! I don't care if they have burst heals or a 3 second god mode, it's part of the class.