It's worse than that. A franchise QB beats the rush more times than not. At the very least he burns them so bad, at least once, that it changes their whole philosophy about rushing the passer. With many QBs you need to control your rush, not allow the QB to get outside the pocket. Lamar Jackson for one. Pat Mahomes for another, for an entirely different reason.
Then you've got a bunch of clowns that you want to leave the pocket because he's going to do something stupid in your favor. Like run the wrong way for 10+ yards, step out the back of the end zone, hold on to the ball while running out of bounds for a loss.
As long as you've got that 2nd type, it doesn't matter how many weapons he's got, doesn't matter how much you spend on the OL, & it doesn't matter how dynamic your RB is. Because that guy touches the ball on every single snap. You're going to rush him with abandon. Pin your ears back on every snap. You don't have to wait for 3rd & long or obvious passing situations. As long as he's got the ball in his hands, if you get him off his spot he's going to do something to help you.