As with so many things these days, the internet gives people the ability to speak to millions of other people. The idiots and extremists seem to garner more attention, and therefore, generate ad revenue; so they have an even louder voice. I don't think there are actually more idiots and extremists, but merely that the few that exist can get together and try to indoctrinate others into whatever bent world-view they have.
He says while typing in the comment section ...
(commented in the wrong place earlier)