Olympic viewing levels are up compared to four years ago. NBC executives are ecstatic -- and even though prime-time audiences for rival networks are down to their lowest levels in decades, executives there are thrilled, too. The moral they're embracing from these giant Olympic ratings is that broadcast network TV is alive and well.

But is that the right moral?

I propose that the proper moral is that broadcast network TV is in trouble, and the high ratings for the Olympics proves that more than dispels it.

That's because the Olympics have given us high-quality, handsomely produced entertainment that's a thrill to watch. From the opening ceremonies to the astounding fleetness of Michael Phelps in water and Jamaica's Usain Bolt on land, prime time on NBC has been, to borrow a phrase, TV worth watching.

For the rest of the summer, though, NBC has been serving up the video equivalent of fast-food junk. And Monday, the night after the Olympics are over, NBC is back to basics -- with the season premiere of Deal or No Deal and the premiere of America's Toughest Jobs. That latter program is a new reality competition series that, on balance, isn't that bad... but it's nothing to bring glory, or Olympic-sized audiences, to network television.

If the networks think they can save money by producing lots of cheaper, unscripted series in hopes of landing a quick hit -- and that's exactly what they do think -- their short-term thinking will lead, inevitably, to continued long-term erosion. The networks all are looking for the next American Idol. But while they're looking, they're tarnishing their own reputations with the likes of Kid Nation, Fat March, Celebrity Circus and Moment of Truth.

Viewers did show up to watch NBC when NBC presented the Olympics. But the real lesson is that NBC has been showing what it's like for a network to act like a network. If they want to be bullish about their collective future, they should embrace that notion by pursuing and presenting quality programming -- not running away from it.