1. Ancient History - Historically politics was a hobby of the elite. You had to go out of your way, sometimes into the cold to attend party meetings. The discussions were academic and professional. People who were involved in politics had their lives very much together, on both sides of the isle.
2. Social Media was invented. I had the opportunity to work with a very fantastic and kind person. My role in the organization was software engineer. This person's role was warehouse operations. Because of Social media this person, who would otherwise never be politically engaged, rocks social media all day long. With the advent of Facebook on mobile, this person tweets political memes all day long. This person spends Xor time on reddit, and "chan" sites. This person now represents the main stream. This person is awesome, but shouldn't be shaping policy.
3. Solutions. I have a number of ideas. I think we should move away from ideas such as ballot initiatives and direct democracy and embrace the fact we are a Republic. We need professionals to determine policy not the twitter mob. Another solution I would seriously implement is a rule. No politics on social media. If its political, flag it, delete it. This would take care of twitters toxicity problem, and facebooks foreign interference problems.
I'm spitballing ideas here, but I am not sure Democracy can survive first contact with social media. It's a mess. people are angry. If you work at one of these big tech companies, I'd love to know your take!