Directv has nothing to do with whether it is exclusive other than ASKING the NFL to allow it to be exclusive. It is 100% up to the NFL as to whether the contract becomes exclusive. If the NFL doesn't want it exclusive then they can choose not to make it exclusive. The NFL CHOOSES to do so because that means they get more money from Directv. But, it is still 100% the NFL's decision.
Using this as a competing argument about Comcast is just wrong.
I doubt DirecTV is only asking. They are probably paying a premium to be anti-competitive.
I think this is more in the FTC's line of work. Agreements that exclude competitors should be prohibited. Since it's gone on for so long, we must need another law. It's fine that the FCC is trying to do us some good, but to me it seems out of their jurisdiction.