I can't disagree with the success of a physically underdeveloped Durant, but I don't know if I can agree that those two scenarios are comparable. We're talking College vs Pro and Football vs Basketball. Not exactly apples to apples.
It's not like they aren't giving Gebbia a chance. He had more pass attempts than any QB in the spring game giving them a lot of things to evaluate him on. But if he's simply lockstep with the other two (which it appeared he was), then you redshirt him give him a chance to adjust to life as a college student/athlete, learn the offense and physically develop. And who knows, maybe he'll pass them both up.
That said, we can also just agree to disagree.