I use to enjoy watching the Steelers, Ravens, and Jags play, back when they were all good. They would beat the living daylights out each other, my kind of football. Which is one reason I really enjoy watching Seahawks vs 49ers games. Both teams try to hit as hard as they can, both teams are kind of throwbacks to the day when football was about the hard tackling.
So we like watching other teams play to see favorite players, rivalries, hard fought physical games, and because we all love football and are starving to see great games.
A blowout is only interesting if you root for the team on the winning side. To most everyone else, it is boring. Unless they harbor some sports hate for the team getting stomped.