I'd rather Rescue not be in the game at all, not have even more people be able to use it.

Not sure why they removed knock backs from DPS and WHM
Because they were annoying and tended to just slow melee damage/AoE down. It was particularly egregious when Fluid Aura / Blank / etc. had damage tied to the skills, because you'd *have* to use them in order to maximize your own damage output, even if it ended up slowing down the output of your frontline.

Even when they removed damage from those skills, it wasn't enough, because people still ended up spamming the skills anyway purely to be annoying.

If you want to hogtie a mob somewhere to be left alone for a while, there's bind/sleep skills for that. Knockbacks just aren't really needed, other than stuff like Masked Carnivale where they designed BLU content specifically around it (and it's fine there, because it's solo content)