Social media encourages more emotional communication. Moderate and calm posts get less engagement than more radical posts. If you want to get more likes and reposts, you should add more emotions. It is quite intuitive and familiar to any active social media user. But the Yale researchers proved it with their experiment.
They researched the emotional status and engagement of 12.7 million tweets with outrage. This resulted as expected: the more reactions users received on their outrage posts, the more similar emotions their put into their subsequent posts.
Likes are the social currency of the Internet, and the position of an outraged moralist makes it easier to get this currency. Of course, such a system of motivation does not contribute to a moderate and serious discussion. It is just more useful for popularity to be more radical in your statements. And it seems that it will not be possible to change this system. Can anyone imagine Facebook, Instagram or Twitter without likes?