Comparing TV ratings between the NFL and any other sport is a foolish waste of time. The NFL is a made-for TV sport, others are not. Teams play one game a week, on a Sunday afternoon when everyone is home and there is no competition for viewers. Baseball plays six or seven games a week, mostly at night on weekdays when families are eating and doing homework and housework, and all the TV channels are vying for eyeballs with dramas and comedies and reality shows. Oftentimes baseball will have a weekday game in mid-afternoon. Of course the ratings aren’t going to be as good as football.
Still, the LA Dodgers were bought for $2.1B last year, and they are creating their own TV network. It doesn’t seem like the big money is worried about the popularity of the game.