I never witnessed Jax, so I didn't understand exactly what you meant.
I watched him play in the dleague a lot though, and what we have seen is pretty much his game, with some major improvements, but the essence of his game is the same. He has added a spin move I never saw in the dleague. I think that is something he worked with coaches here in SA. He also didn't do that preseason or SL and it helps him avoid being cut off or turning the ball over, as well as takes advantage of his quickness, so I believe he's still improving despite his age. His handles are probably not going to be great ever, but he is better anticipating swipes and seeing the guy who is going to cut him off and at that point grabbing the ball to shield it, even if he has to cut his drive and take a shot close to the basket but not at the rim. He's so athletic that when he jumps he still has a good look at those shots.
I definitely have seen improvements, but the kind of game you mention, he didn't have it. He was not a prolific 3 pt shooter. His made shots were wide open, and set. He's improved his shot, but he's not the kind of guy like Kawhi or Manu that you want taking freelancing shots, step back jumpers or what not.
I don't see the deferral you see, except that he won't force shots that are beyond his skill at this point. If he has a lane, he will take it, if he has a 3, he will take it, he will pass well. To freelance on his own requires I believe a more sophisticated offensive game than he has.
You know who has that kind of sophisticated game? Slow-Mo. He does defer too much, he is much more skilled than he has shown and he does and did defer too much, but we are not a development team. We are a contending team, so he will have to push the envelope and develop whenever he can.