I look at it like this:
If you swap them onto each others teams, what does that look like? I think Breece does far better on those Davis teams than Davis does on Breece teams. Breece is just so much more complete. IMO Davis didn't do anything in the NFL because once he was facing a whole team of NFL tacklers, his greatest attribute was severely diminished due to his lack of raw physical talent. That's not to mention the mileage he had on him. Who knows what Breece will do, but there isn't a measurable deficiency that he has. He has everything you want, especially in the modern game.