I've long since accepted that Yasuo will probably always remain the nuisance that he is, and that's whatever. Ten bans are close so it doesn't matter all that much.
At the same time there is a nerf that he does need. That whole blink outside of range if you ult under turret? I'm not even a novice at balance and even I can see that this is an unacceptable power for someone like Yasuo to have. If
Yasuo wants to turret dive he should have to take the risk like the rest of us.
EDIT: Can some of you read what I'm writing please, and not get triggered just because you saw "Yasuo" and "nerf" in the same sentence? The only change I am asking for is for him to suffer the consequences of turret diving an enemy, just like everyone else.