Coaching in GB is a pretty big stage, hell SB trophy is named after a packers HC. Like Dallas, GB has a long and rich history
Green Bay has a lot of fans and a national following just like Dallas does, but being the coach of the Packers is NOTHING like being the coach of the Cowboys.
The local press cover the Packers are more like a college team, rarely critical (I mean how can they dump on the only thing going on in Green Bay?), never probing, and mostly cream puff questions.
The sheer isolation of the place (even Milwaukee reporters have to travel 2+ hours to get there) and lack of any owner looking over one's shoulder allows a coach to pretty much go about his business without anyone questioning him.
It will be very, very interesting to see how Mac responds to the much increased scrutiny he will be under while coaching America's Team.