Without attack speed early, he suffers greatly. He's been nerfed over the past year to remove his early game bullying by a massive amount which was a lot of the reason to pick him; but the entire paradigm of a no downtime crit champion with a windwall is toxic even when it isn't powerful. Windwall needs a clarity treatment of canceling particles behind the area and not the whole ability. Personally though, I am fine with it stopping ranged champion auto attacks. The issue I have is how hard it is to see on its base skin. Much like Luxs base skin and Legions particles.
That is a tangent however. He simply needs more base Attack Speed is all. Already has horrible base stats so he gets blown up later if he isn't good, so compensation nerfs can wait until after if needed at all.
The issue is when it is good, it feels awful to try and outplay a champion with far more options of approaching a situation than you that is approaching it even remotely well, hence prior nerfs to make that ceiling harder and the early game less oppressive.
I miss the Yasuo who could start E, that's basically dead. Can't hold onto a tornado to dissuade a Zed ult or have any real damage this season before practically 2 items on him. But you know, as the years go by, solo carry champions get slowly toned down. As is progression, can't say it wasn't inevitable. Side note that I don't play Yasuo too much, but nor have I ever had any serious problems laning against Yasuos in Platinum and Diamond. If I'm playing a mage who can't kill him easily, I can manage the wave to not fall behind or wait for the jungler. In the end, his responsibility is higher in a teamfight to the variables of success whereas most mages are lower with just as much impact, some with more. When he gets fed, it feels preventable unlike a Syndra ultimate, or even a Zed ultimate or even Rammus [which are all preventable, but with a much higher degree of effort required). I feel like it's just the Windwall that holds him back from real base stats honestly. It frustrates so many people.
