National guys are paid to be neutral. Fans expect the local sports media to at least mildly like the team or have some interest in them. If not you get mediocre programming like we are currently seeing with cowboys . I have traveled all over the country and your better fan bases (Pitts, Balt, NE, GB) have sports media who are absolutely not neutral. One thing is certain, in those cities I mentioned they can't talk enough about their team. In Dallas its a choir for them to keep the talk about cowboys.
You can't compare Dallas-Fort Worth reporters with reporters from Boston, Baltimore, Pittsburgh, or Green Bay. Those cities are all smaller than Austin, let alone Dallas. Local media in real cities like New York, Chicago, and Los Angeles are critical of their teams when they are bad and reasonably neutral when they are good.
As an aside, it's bad for journalism for the local media to be anything but neutral. The only major sports team from a large city I can think of that are actually super darlings are the Chicago Blackhawks. Chicago local media ate that stuff for breakfast, lunch, and dinner. It was borderline insufferable. More importantly, none of the local media had any reasonable coverage of the Patrick Kane scandal due to their love affair with the Blackhawks.
Moral of the story, this is Dallas, the biggest football team in the country. We have enough fans, we don't need the media to slant, as well.