She's not faceroll like she used to be, but because of her resets, she's by far the easiest champion in the game to get pentakills on. I actually got one a few hours ago, but it didn't really feel special or anything, it's just a thing that happens every now and then.
I find the majority of people who complain about her don't know how to play against her. Like I've seen people complain about her lvl 2 or 3 all ins which is just absurd from my perspective. At those levels, shunpo's cd is a full 2 seconds when picking up a dagger which is a lot of time to be punished in lane by the enemy's ranged autos and their minions if they positioned correctly.
These are the people that don't seem to realize that Kat cannot guarantee her dagger pickup damage on someone without a gunblade active, and if they dodge them, they auto win all trades. Once she does get that gunblade, most mages should generally have the tools to waveclear efficiently and safely.