It all seems to come back to a "contempt prior to investigation" mindset. Just about everything in print (on screen) is someone's opinion. Declarative statements have a tendency to backfire. If you watch any type of televised competition (I'm a fan of "Chopped") one contestant will say to the other, "You're going down!" only to lose the match a few minutes later. That's just a game, but In business and media this is becoming a big problem.
As an editor, I often correct writers who sprinkle declarative statements, along with stereotypes and generalizations, throughout their manuscripts without realizing the impact they are having.
I'm also mindful about looking into deeper facts for opposite viewpoints when I see claims such as, "11,000 scientists across the world declared a climate emergency." First of all, the 11,000 just added their signatures to an online petition of sorts. And after a deeper look, the 11,000 "scientists" were not really climate scientists. The sample showed the signatures were from, "professors of psychology, managing directors of private companies, medical professionals, specialists in environmental politics (not science), computer analysts, a nephrologist (study of the kidneys), nutritionists and a techie at IBM."
Yes, people should slow down to wait for facts. Some never will until they get caught; some of those won't care and continue, because information is moving too fast for most people to keep up, meaning we will soon forget. But it's also my responsibility to do my own research. Because what lingers, as you point out, is the anger that was spread along with the misinformation. Feelings remain long after facts fade away.