Campbell is an Ohio native and a heckuva leader. But the Browns would not be able to sell their fan base on that given their long term futility. As of today, Campbell is 18-18 as a P5 head coach and no NFL ties. A coach of an improving team that hasn't won anything yet, not even a conference title. It would be a WTF hire only slightly less than making Condoleeza Rice their head coach.
Now, if Urban Meyer ever leaves OSU, and there is some speculation he might, I'd be more worried. But even that would be a hard sell to their fan base unless ISU really improves a bunch more in the mean time.