Why is Qiyana's knockback not a CC, unlike every other knockback in the game?
There is literally no other knockback in the game that acts like this.
If Qiyana hits a champion with her ult, they can continue to use abilities that don't have a cast time until they hit the wall. For example, if you ult Zed, he can ult you at any point before impacting the wall and avoid being stunned, even though he didn't juke it. The same goes with Kayn's ult.
It also doesn't stop movement abilities. I had a game recently where a Hecarim was running directly down mid lane and trying to dive me. I ulted him away as he started his E dash. Even though he didn't connect, it still 'hit' me, and instead of pushing me towards my turret, it pulled me in the same direction as Hecarim, away from my turret. I'm sure there are a ton of other unintended interactions like this.
Why not just make Qiyana's ult act like everything else?