I think its over for him. Any respectable DC knows all you have to do is confuse him with coverage, bring 4 and have a LB spy to stop the run. His "coaching" comment and just "needs to play free" really show that the game is too complicated for him and he is at his best when he tries to out athlete everyone. The NFL has seen the one-trick he has and now gameplans around it.
Now I think the Bears could use him way better, but I still believe their desire is to see if JF can be an NFL QB or if he is just a running back that can sort of throw.
I think its way premature to say this... his one trick, at least right now, isn't too bad, and was uncoverable last year. It was admirable to want to refine and streamline his game into something more fundamentally sound, but he was a vick level runner last year, it took him time to piece together the whole package, it took randall cunningham time and they both became plus passers and processors of the game.
Watch some Zach Wilson to see a guy who has no processing power between the ears, unbelievably terrible. I don't know if Fields will ever be a top 10 NFL QB but if he flames out this year, I'd certainly give him a chance if the Bears are picking Caleb Williams.
I will say this, the Bears coaching looks to be total garbage and doing him no favors