Yasuo is op. Just listen.
So I just had a match as katarina where I ROFLSTOMPED my lane. I went 27-8-19 I think, and guess what? Their yasuo gets static shiv and all of the sudden he's dealing fricken TRUE DAMAGE. You can't outplay him since his only skillshot has like a 1 second cooldown at endgame so basically no matter how much you SHUT DOWN THIS GUY EARLY, HE WILL KILL YOU. I should know, I crushed him early as katarina, then when he got a couple items, got 100% crit chance and we couldn't even build defensively against it. Yasuo is op because: At late game he deals true damage 100% of the time. There is no way to counter that with items, and no way to counter it with champions.