Cam Newton can't be Cam Newton if he can't run effectively.
But if he runs effectively, he gets beat up and hurt and it affects his ability to throw.
In other words, it's a lose-lose proposition. So, the young Newton that got the crap kicked out of him is now in mid-career and he's not the same guy physically or mentally. The longer Carolina sticks with him, the longer they're going to be a middling team.
This is why I'm so anti running QB. I know when they're real young, and they're running around out there dazzling the fans and the media that they're all on the road to Canton. So why do they never make it? It's because the NFL game is too physical and brutal for running QBs to survive very long.
Yes, you do get the occasional exception to the rule (Russell Wilson). But he's just entering mid-career as well, so we'll see.
You can't survive long as an HC or GM by betting your team's fate on the exception to the rule.
So for B-More, Carolina, Arizona, Chicago, and perhaps KC, you better have plan B at QB ready because you're going to need it. The decline happens almost overnight.