I think the key benefit of a narrow selection of live programming is the idea that a lot of people listen to the same things. The discussions that follow a program, between people who watched or listened to it (which could be a significant chunk of your friends or coworkers) is to me at least as important as the content itself.

With podcasts and streaming I often find the discussion starts and ends with "yes I listened to an interesting podcast about that...". Perhaps that will make someone else listen to it the next day, but the window of opportunity for discussion is gone.