Riot "BIG BRAIN"

Okay, so I just want to want to say this, I am an Ahri main, I love her. She is by far THE GREATEST CHAMPION IN EXISTENCE when it comes to burst potential and the enemy team not being able to to anything about it, because you know... charm. But there is one thing nagging me, and it isn't necessarily about Ahri's burst, in fact, this issue isn't even about Ahri at all (except she is though.) This post is about Lux... The 2nd and below category of burst potential. in fact this is about her ult... Why isn't it cancellable, I mean you can cancel it if you kill her while in animation, but why not when she's charmed? (This is why I started with Ahri) And not just Ahri's charm, but Eve's and Rakan's. They can't cancel it. We Charmers can cancel basically all abilities in animation -- except a few I can understand -- all... except... her. And specifically her ult. Why doesn't stuns, silences, and taunts work on her ult either? This also is a thing with Ezreal too I believe. It might just be some sort of thing with her lore that we will never know about. I might just be ranting about something that Riot has already said why and I would be looking like an idiot because I never did my research. But even then It still doesn't make sense to me, I just don't understand why you can't cancel that thing.