Television Encompassing Discourse

In the sixth chapter of "Amusing Ourselves to Death", Postman talks about how "television encompasses all forms of discourse." He gives three examples to justify his statement: "No one goes to a movie to find out about government policy or the latest scientific advances. No one buys a record to find out baseball scores or the weather or the latest murder. No one turns on the radio anymore for soap operas or a presidential address." I agree with Postman's statement because people can turn to television to find out about these things. He says that television is how our culture knows about itself. Later, Postman reveals that the message of television is that all the world is a stage. I wanted to raise a question regarding this topic. Do you agree with Postman when he says that "Television encompasses all forms of discourse"?  Thank you for your time.