[mr-wendel]

I think you answered your own question. Prime time TV = prime time entertainment slot.

Consider that by knowing someone's preferred source of news you can typically predict their political views with 90%+ accuracy, particularly if we're talking prime time broadcasting.

The news is meant to entertain: "To hold the attention of (someone) with something amusing or diverting.". To grip you, you're told stories about "your team" and its triumphs and tragedies. Sport is a relatively simple and benign aspect to all this.

In general (and some sports coverage does this), the rest of the recipe calls for outrage against "their team". It calls out their shenanigans and instills a sense of superiority over them. And as there is literally nothing you can do about any of this the only goal is to keep you coming back for more.

Perhaps in the past (... get off my lawn!) there were more attempts to inform people in a neutral sense. Maybe even to help people challenge their thinking and their bias so they're better equipped to negotiate disagreements in matters they can engage in and affect.