What has happened the last few years is toxic AI algorithms on Youtube and social media amplify extremist views and conspiracy theories and worsen people's mental well being.
Indeed. Questionable rationality of individual people is one thing, and there are plenty of mental health conditions which can affect human rationality. Aberrant biological processes which affect brain function and can lead to mental ill health: the bulk of mental ill health is likely underpinned by physical brain problems, which cause incorrect wiring and incorrect information transmission in the brain.
But then there is also the very important issue of how human brains are "wired" together though the Internet and social media. Not many people are cognizant of the fact that the Internet and other electronic media is emerging as one giant planet-wide brain, where individual human beings are like neurons of this brain. We might call this the Big Brain of humanity.
If the way humans interact on social media is not set up properly, then the Big Brain itself becomes incorrectly wired, and then the Big Brain can become insane. Viral spread of hearsay and unproven wackly ideas on social media is a bit like schizophrenia itself, and can make the Big Brain go mad.
In schizophrenia, people start to believe things that are not true, because schizophrenics lose the ability to perform proper reality checks.
For example, a schizophrenic person might it get into their head that all Amazon delivery drivers are working together in an evil scheme to kill them. Once they have this idea, they cannot let it go, because they cannot do the normal fact and reality checks that sane people are capable of.
It's a totally wacky idea that Amazon is out to kill you via its drivers, but a schizophrenic may start to believe it, because the psychosis symptom of schizophrenia prevents the brain from doing normal fact checking. So this idea of evil Amazon delivery drivers may remain in the mind of a schizophrenic, and he or she cannot let go of the thought.
If we return to our Big Brain analogy, viral spread of unproven wacky ideas on the Internet is just like the psychosis of schizophrenia. All sorts of wacky ideas come to life on social media, and zap around the planet by viral spread (social media retweets, shares, etc). And in this way, the Big Brain of humanity can develop a psychotic mental illness.
It is thus very important that we start properly controlling the way information travels on social media and the Internet, to prevent the Big Brain from going insane. If Big Brain goes insane, then the consequences for human society are significant.