Okay if one’s intense historical time horizon is no more than 15–30 years and one is buried in today’s social media, then of course one would have little basis for knowing what is true and what is not.

Few people have the intellect (the ability to see the big picture, not to be confused with IQ smarts) to know what truth is because in order to rise about one’s inherent tribal impulses requires lots of enhanced intellect.

What you are really pointing out are people’s various conflicting tribal impulses of race, gender, geography, religion, age and political party conditioning, etc.

Some of us, however, are not knee-jerk tribal homers (true believers) and we can perhaps 90% of the time accurately ferret out what is real and what is fake news.