Talking only about open world, not instances of ANY kind here.
Open world bosses can be squishy enough that my mirage can already kill a bunch of the rando champs which spawn in almost any zone.
The might sharing, torment build I use doesn't even have much in the way of CC or even AoE damage.
Even my confusion attacks don't seem to make much of a dent in the defiance bar. My reaper or scourge can wreck a bar (not talking about a drinking establishment, that's an IRL situation) with several different skills. My mirage doesn't need to. It's a DPS machine.
I understand the desire for all these soft CC skills in your armory to have an effect. They are useless against a champ (I'd love for my reaper's chill to slow a champ) but the temporary knockout you achieve when hard CC breaks the bar is the trade off we make.