Wiz can shock mobs, and have shield to absorb 60% of the damage. Taos can hide, summon pets and run off. ShS also fails a lot when mobs are around you / hitting you , so suffer the same.
See I think your not getting my point though, I play sin too. So im fully aware of how often SS fails. But in the case of early days in archer room as you mentioned, a wiz with this current flinch would almost impossibly fail. Let alone before.
Wizards cannot tame ranged mobs, you know they still attack, very similar with Hide, often range mobs still see through this.
My point is that stun lock removes any chance, I don't think there should ever be a stun lock situation, im not saying put the old flinch back, im saying look at removing getting altogether stuck so you cannot move because of flinch