Bad habits are incredibly hard to unlearn.
(This is also why, you don't need to run at all for PA to work.)
Wilson never needed to learn certain parts of being a QB, both because what he did already worked and because it was probably near impossible to do so. We had a good line during the SB run. But Pete loves to put UPS guys, TEs, pizza deliverymen, etc in at the line instead and just have them dive at the defender's knees. (There used to be a hilarious video of this where a bunch of the Seahawk offensive linemen jumped on the ground and were rolling around in the grass while the defenders were just standing there.)
While Wilson left clean pockets regularly, his pockets were not consistent. Even when the blocking succeeded, it could not be relied upon. OF COURSE, he left clean pockets.
By now, he probably lost the opportunity to get better at the other stuff. And frankly it was only until recently that defenses have been able to solve the mobile QB problem. This is why Mahomes was struggling for a bit too. Defenses were changing.
Wilson was running a passing offense that asked him to make reads after the snap based on the type of leverage the CB applied. It worked.
Combined with the option for the QB to keep the ball, it was tremendously effective.
Can Wilson do the other stuff? Probably late to learn. We will see. He did the year he was injured (2017?)
But it made no sense for him to do so here.
To be fair, a less obstinate or intractable coach could have found a way to make what Wilson did well work for him. The same way the younger Pete did. But it stopped working once Pete started forcing what he wanted to do, regardless of roster, scenario, or even opponent strengths/weaknesses.
I suspect Wilson will struggle in Year 1 as he learns his new team, and everyone here will chortle & point, thinking it validates their conclusions. Then Year 2, Wilson will have a resurgence, and everyone will be scratching their heads - while Pete struggles to make whatever flaming pile of garbage we are then trying to call a roster, work for him here.