Is television really dumb? Absolutely.
Is this a change from before? Absolutely not. There has never been an era where network TV has been intelligent. Have you seen Nick at Nite? We romanticize old television because we weren't alive then and we've only seen the standout exceptions like Twilight Zone.
And premium channel TV shows are way more intelligent than any other era of television.
It is a shame though that learning-oriented channels are getting desperate enough for ratings to dumb themselves down.
And yeah, reality shows have writers. They don't script the characters, but they script the situations.
You know how they all have the disclaimer "Portions of the show not affecting the outcome have been edited"? Yeah. Even before The Apprentice turned into a celebrity crazyfest, Trump discussed his firings with the producers.