Centralized because running a press or a radio tower is expensive. For the same reason, there were a smaller number of channels, and a more unified discourse (e

Centralized because running a press or a radio tower is expensive. For the same reason, there were a smaller number of channels, and a more unified discourse (everyone reads the same newspaper). Now, neither of these is true. Twitter, Facebook, etc can customize the feed to every user to maximize engagement. At the same time, whatever doesn't fly politically at corporate HQ can be restricted, with as much or as little visibility as they choose.