The dual political alternative reality universe has been getting some coverage.
CNN's Brian Stelter alleges a dual alternate universe and that GoP is the unreality v Dan Bongino, that the liberal universe is unreal. https://rumble.com/vhlrk5-ep.-...
A cause in my opinion is extreme idealism and utopianism, which overrides and is immune to facts. One can also stir in the Neo Marxist 'social construction of reality'.
The media and Big Tech have exacerbated this trend and have abandoned their duty to factual inquiry. Where the narrative and opinion are more important. Dan Bongino illustrates the point with the 'defunding of the police' narrative which has lead to death and crime rate spikes.
Opinion over truthful inquiry is a point made by Socrates in The Republic and The Phaedros.
The problem of over heated idealism and utopianism has been noted in Classical Athens.
Plato in the Republic had already covered this. The following quote is from the late Allan Bloom's commentary to his translation of the Republic:
"The proper spirit of reform, then, is moderation. Socrates constructs his utopia to point up the dangers of what we would call utopianism; as such it is the greatest critique of political idealism ever written. The Republic serves to moderate the extreme passion for political justice by showing the limits of what can be demanded and expected of the [polis]..."