The article spells it out rather nicely: 18% of republicans trust the news. While 43% of Democrats don’t.
Most of this mistrust is coming from the right, despite what many ppl like to claim, NPR isn’t objective or impartial they’re fairly solidly left. All the “institutions” that many like to think are giants in the media are really pretty much just mouth pieces for one side’s politics, the right has Fox News and the left has NPR, NYT, etc. They’re both distrusted by opposing sides for the same reason: they don’t report the news.