The thing that needs to be understood about any National Media personality is that they need listeners/viewers/people talking about them. There are two ways to get this, love, and hate. Love is great but the team/school has to give you a reason to speak well about them, and most teams don't do this consistently. Hate is much easier, it takes very little to hate on something, pick anything and go after it hard. You don't even have to know anything about a team/coach/player to hate, you only need one little negative snippet and you can go after them.
Wilbon probably knows Iowa fans are passionate, and not many have any reason to pay attention to him or talk about him. He can draw Iowa fans (or any school's fans) in with love (like Mark May/Bob Davie years ago) or hate, and chooses hate, because it's easy. He has to know very little, can say a few ignorant things, and it gets him more buzz than money could have bought. You can probably throw Dakich in the same category, though he seems a lot more educated about the teams he covers.