You're conflating two very different environments. Mass media of yesterday was the establishment broadcasting carefully considered things. Social media today is

You're conflating two very different environments. Mass media of yesterday was the establishment broadcasting carefully considered things. Social media today is individuals chatting to other individuals in a manner that can incidentally be seen by everyone. People using say, hackernews, aren't modelling this interaction as if they are on the stage being broadcasted to the world, they are modelling it as if they were talking to someone at a pub.