The media reports the "news" -- those who yell loudest. This has been true since AT LEAST the middle 1960s.
As a result groups and people have learned to exploit the media, to turn it and twist it so that it reports what they want it to report. And you don't have to be a billionaire to do this.
Abortion, gun control, immigration, airport security, gay marriage, and a host of other things have prompted "dialogues" in which one side simply castigates the other without listening to each other. A dialogue in the media has become two monologists talking to an audience.
And the audience all too often is made up of people who believe as the speaker does, and who associate only with other such people, and so they believe that because all of their friends think so EVERYONE must think so.