I don't entirely disagree with your "unpopular opinion." The coaching DEFINITELY matters a TON, as does surrounding talent, but I agree that a QB prospect's own drive and ability to process criticism and failure with humility, while also maintaining the confidence necessary to perform under duress, is/are the most essential component(s). It's a rare combination of factors that coalesce to allow a young QB to improve and excel in the NFL.
Caleb Williams appears to have some REALLY bad tendencies to hold the ball and to throw from bad bases too often. His insane arm talent is probably holding him back, in that he can sometimes make the impressive, improvisational, off-platform throws, and that skill (along with his scrambling) has got him to this point in his career already. So he seems aloof or resistant to change. There is reporting to back up this perspective, if you find that reporting compelling.
Very interested in where the Bears season goes from here. I have a lot of respect for Ben Johnson's acumen and aggression, and have at times wished for him to replace McD. Like a Dungy-to-Gruden type of transition.