I'm not certain but in considering your question I came to: Political polarization is a network of cognitive biases which decreases mental models' connection to the reality that people agree on more things than disagree.
"This 2019 internal report obtained by Haugen says that the parties feel strongly that the change to the algorithm has forced them to skew negative in their communications on Facebook ... leading them into more extreme policy positions." (8:07)
Although the above statement is from a group of European politicians, it's not hard to see the same story playing out in the United States. Take the Covid-19 pandemic, for example. The impact of partisanship on this issue is as clear as day:
"There's A Stark Red-Blue Divide When It Comes To States' Vaccination Rates"