I can agree with this 100%. This is why we have better coordinators than actual quarterbacks and why we look for athletes than can throw. What you described coincides with the decline of actual quarterbacking in the NFL (along with the lack of development in college).
Different QBs have different skillsets which does not fit every offense and this doesn't translate across the board. Not to mention the fact that we never take into account what these QBs are required to do in each system. Lamar Jackson and Josh Allen being asked to play in a pure progression, traditional pocket passing offense would be ugly..lol. Fit matters and always have...
What if I told you that a lot of the "off script" element comes from these quarterbacks missing reads all over the field..lol. The irony of this is....
the offenses that Mahomes, Allen, Jackson, and Daniels run could be said to be the easiest....