I disagree with this premise, though it is not unreasonable. However, I don't think Bradford is more predictable, he's just unreliable in different ways.
Edit: I think part of this is Bradford "looks like a quarterback." Though that can be racially charged (hi Bill Polian), I don't intend it in this instance. He drops back, sets his feet, and throws the ball. That's what plenty of people want, but I think part of that is comfort level with the traditional aesthetics.