"Yasuo's 2nd passive shield was to allow him to survive as a melee champ in mid lane"
Yes, thats true. Yasuo was originally designed to be a Mid champion. That made sense when he was laning against ranged mages.
However, the reality of this situation is that he is a majority top laner now. His shield just allows him to abuse melee champs for guaranteed winning trades before he uses his insane lane mobility to get away before you can properly retaliate.
His shield just makes his early game much too strong considering he scales extremely hard into late game. He doesnt even have a weak Mid game because
(only 2550 gold) is such a massive power spike on him.
So we're in a similar position as we were with Ekko. A champion designed around mid lane gets taken top where he wasnt designed around.
Possible solution: Attach his passive shield to his Ult. When you put your first point into your ult at 6, you regain his passive shield exactly as it functions now. This gives us at least a reasonable window of opportunity during his early game, which is supposed to be weak.


or
.
. That was when we were close, but Tankko was something completely different. Ekko, at that time, didn't even build in the class of items he was supposed to, and built tank. Yasuo will never have that problem again because of the changes to his Ult armor pen and a few of his values. Tankko was an accident. They never even imagined him being taken out of Midlane. After a few patches, and this assassin rework, hes back to the Midlane.