I'm not sure. I think you underestimate how getting tougher can make for good TV. This doesn't mean, of course, that they will ask them anything substantial: just stuff that will prod them to react. e.g. Rezko is completely irrelevant except that it scrapes away a little of the Teflon. The real scandal is that he's not going to do a damn thing differently. And they won't touch that because they're in on the marketing campaign. The narrative is already set: now it's just about the details. Throwing some questions like this is a way to see the protagonist overcome adversity. Since they think they know how the story ends--and their main role is to legitimate power--I think you're right in the long run. But that doesn't mean they can't have some fun in the meantime.
s