I see a lot of shows have 20 mins content for 10 mins of commercials. Does this heading mean, that kids were watching 1200 hrs of TV a year? That is almost 3+ h

I see a lot of shows have 20 mins content for 10 mins of commercials. Does this heading mean, that kids were watching 1200 hrs of TV a year? That is almost 3+ hours a day. Isn't that too high? Note: I am not a parent.