you misread it, it was the highest rated TV program of ALL TV programs not just NFL Games...
Not only was CBS’ broadcast of Sunday’s AFC Championship Game between the Patriots and Jaguars the most-watched game of the season, it was the highest-rated program on television since New England’s epic comeback against the Atlanta Falcons in last year’s Super Bowl.
Again that’s normal. Only the Oscars and World Series would come close. A low rated NFL playoff game still beats all scripted programing.