I suppose 1 way to explain things is a limited QB. But as G neared the end of his SECOND year in the system, if he still needed the Cliff Notes version of the offense, then I am not sure that says much for Goff.
Personally, I always felt that the onus placed on Goff was overdone.
He started missing throws, and that apparently was connected to reads he was not expecting. And he does hang onto the ball and fumbles. Both would seem to naturally improve with experience.
But watching those games last year, I just felt I was seeing defenses sitting on what we were trying to do. I felt it was more that than Goff needing training wheels.
But, who knows? Maybe your read is correct. Whatever the reason, we need a broader palette this year.