"The problem is that facts—at least today—are themselves subject to doubt, especially when they conflict with our political beliefs (21). In the past decades, America has seen a decentralization of news and information (22) that has allowed people to gather their “own facts” (i.e., alternative facts; ref. 23). Most recently, claims of “fake news” allow people to distrust any information that fails to align with their political beliefs (24, 25) and to trust fake news that aligns with their beliefs (26)."
This is the epistemic crisis we're currently facing. Up until about the late 70s we had 3 news networks that were all pretty much middle of the road politically. Newspapers could have more of a discernible political leaning, but even there most of the mainstream ones we're pretty centrist. People who hewed to an extreme political position in either direction were ostracized and thus had a very small audience. We had more of a common narrative which is now gone.