Your impression is correct. There are about 1.5 touchdowns per every TV hour of football and 1.4 goals scored per every TV hour of soccer.
Ten minutes of actual play over an average of three hours, ten minutes of TV time. One minute of NFL play per ten minutes of TV time. Thirty-one plays will be kickoffs (50+% of which will be touchbacks), field goal attempts, kneel-downs, or punts (25%+ will be fair catches).
Yet they say soccer is boring because there aren't enough scores? Isn't it boring when there's no play 90% of the time?