“If people in the media cannot decide whether they are in the business of reporting news or manufacturing propaganda, it is all the more important that the public understand that difference, and choose their news sources accordingly.“
If you know how media works, then you know that a great many journalists are believers and want to make a difference. This means they have a built in bias. Dr. Sowell is absolutely correct, you need an array of news, an array of opinions.
In fact, the best of all worlds is for diverse opinion to argue and fight. Let the audience decide what is true.