The system began with cable news imo.
It was in the 90s when America started to become deeply polarized.
CNN, MSNBC - 24 hour hate on anything Republican, excuse everything Democrat.
Fox News - 24 hour hate on Democrats, spin positive everything Republican.
They are all 24 hour misinformation, deceit and hate.
James Wood Wednesday - "one thing that is crystal clear with this election... America is evenly divided, with both sides convinced the other side is insane,"
The "system" began with Republicans abandoned the truth and started promoting the "urban" and "rural" divide when Reagan was disparaging the War on Poverty. It began when the Fairness Doctrine was allowed to expire and talk radio turned into "hate the left" radio. It was further exacerbated when Newt Gingerich was elected Speaker and began demonizinig and attacking the Clintons.
Last but certainly not least, the attacks on the left increased when FOX News started lying about everything the Democrats did. FOX News has been a corrosive and anti-democratic force in every nation where Rupert Murdoch has a strong foothold in the media.
Countries with a Murdoch owned television news network, have issues with racism, immigration, and lies about the left. Countries with no Murdoch owned media have an better informed electorate, who don't believe lies or misinformation.