Not GP, but I propose doing absolutely nothing.
There have always been tabloid newspapers, underground conspiracy theory magazines and various AM broadcasting stations peddling all kinds of nonsense.
The internet is just a new medium that’s joining the club.
There is no substitute for critical thinking. There are always going to be people who will hold opinions that are anathema to your beliefs. Often, those opinions will be the majority and you will be in the minority.
You learn early in life to ignore the crazy people on the sidewalk holding up signs and screaming about lizard-men running the government. You also learn early in life that politeness and civility will carry you a long way towards being respected in your community.
The internet is no different.
If you can’t function without a school teacher in the room, you aren’t ready for the adult world. We don’t need facebook or twitter or anyone else babysitting us as we go about our lives.