The issue is that people are not rational actors, and their emotions can be manipulated into forming new habits. In this case, facebook's goal is maximizing tim

The issue is that people are not rational actors, and their emotions can be manipulated into forming new habits. In this case, facebook's goal is maximizing time spent on site. They know if they get you into a state of emotional flow, you'll stay there for much longer. That is the purpose of ranked newsfeed. Companies just make the "relevance" argument, because it's not wrong, it's just not the whole story. Specifically, if you had a passing interest in a controversial topic, the algorithm will make sure to sink its barbs into you, and exploit you emotionally. This is especially real for older people who didn't grow up with the internet, or people who are blind to this issue. These two groups haven't learned to moderate their emotions and question the nature, or source, of the content.