She's a lane bully that scales insanely hard
Vayne scales harder and is a better hypercarry lategame than Xayah is.
Also most of Xayah's damage relies on her positioning and yours. Don't be in front of her feathers, kite her, and a lot of her damage is useless. If she can't land feathers with her E on you, she's as good as dead.
has some of the best team fighting and disengage of any adc
She's incredibly immobile and once she pops her ult she'll be the easiest target on the enemy team.
are just a few examples of champs that can stick to her like glue easy in a fight no matter what she tries to do.
Is also a helpful item as it reduces the duration of her snare.
If you get E'd and chunked, it is entirely your fault. A good Xayah knows how to position her feathers, all Draven has to do is hit you with his axe for that same damage early game.
As someone who mains support/adc, plays a lot of Xayah, and has supported 2 friends that main Draven, her damage early is nowhere near Draven's unless she's consistently landing E's on you, in which case, you're either bad or she's hella good.