Fake news is due primarily to the serious loss of trust in established institutions. Far too many have abandoned traditional ways of arriving at the "truth." Since "truth" is fundamental to the issue, let me analyze fake news from a philosophical perspective.
One of the preeminent ways of acquiring valid knowledge is by means of expert consensus (historically known as empricism). "Truth" is that with which a group of independent, well-qualified experts agree. More generally, it's the average of independent data, observations, etc. The tighter the agreement between the data, experts, etc., the more that the average is regarded as the "best approximation of the truth."
For example, the "body of 'reputable scientists worldwide'" is in strong agreement that human activities are largely responsible for global warming. Thus, that humans are responsible for global warming is essentially settled.
Those who are susceptible to fake news--especially conspiracy theories--generally start with a set of "preconceived truths such as "one can't trust the biased news media, etc." These "truths" are so strongly held that they are incontrovertible. One then works backwards to find sources that unequivocally support one's predetermined views. Instead of using independent journalists who are experts in seeking out facts and counter checking them meticulously, one gravitates--indeed, seeks out-- instead towards groups of partisan advocates, i.e., "favored experts."
Well-known cognitive biases are paramount in both forming and in confirming one's favored beliefs. Confirmation bias--deliberately searching out those sources that support one's favored conclusions--is predominant. So is cognitive closure. One's preferred truths are impervious to modification.
With the growth of social media, one cannot counter fake news merely by presenting scientific evidence and engaging in reasoned argument. Scientific evidence and reasoned arguments are generally rejected. Instead, one needs friendly, trusted faces that can embed scientific evidence in compelling stories.
If social media were truly responsible, it would deliberately develop sites that were devoted to countering fake news. It would also hire editors to ferret out fake news. In addition, it would employ reputable scholars to test what's most effective in countering fake news.
We're naïve if we think that "scientific facts" alone will counter fake news. It wouldn't exist if it didn't fulfill deep emotional needs.
To respond to such needs, we need to bring Jon Stewart out of retirement to host a new show along the lines of Fake News Exposes! Stephen Colbert is expert enough to take on the job as well!
In the end, fake news is anything but a joke.