He's just not a good enough player. It's sad and unfortunate, but his swing path is FLAWED and the Blue Jays did not realize it until now.
I don't actually KNOW any of this but my guess is that when you have a 1st percentile attack angle, your timing needs to be even better than the average player because of how your swing path lines up with the trajectory of the ball. Every pitch is coming into the zone moving down, right? The typical MLB swing is going to approach the ball at a 10 degree attack angle; a slight uppercut. That means the sweet spot is moving at that angle when it makes contact. Which also means that it matches a ball dropping at that same angle. So that player can be a bit late or early and still put the sweet spot on the ball.
It seems like Vlad does not have that benefit. If he is a bit late or a bit early his contact quality suffers more. It's like his sweet spot is not on plane with the pitch for as long as it is for a standard slugger.
He needs new hitting coaches and he needs to spend the entire offseason rebuilding his swing so that his attack angle is more normal. And I guess a bit more tilt would be nice, but I am not comfortable thinking in an additional dimension.
Ted Williams always preached a slight uppercut swing.
Vlad is the product of some pretty bad hitting philosophy. This is not even complicated stuff.