I think this is just a sign of the coaches getting frustrated and agitating more publicly for punishment.
He's been quiet publicly and played the role he was supposed to play, as most have, but the Big Ten still sits on its hands. That inaction, coupled with some brutal refereeing, has him wondering when somebody with some power is going to fix some of the broken shit in this conference.
All kinds of rumors that something was going to happen to Harbaugh today. I imagine many coaches in this conference are getting tired of waiting.