Everyone has a plan until they get punched in the face. A lot of social media dynamics are not reasoned arguments, they are the product emotional outbursts which can be manufactured and herded.

The world is not made up of Spock-like rationalists, and although most people are capable of rationality, many social settings are not conducive to it. Look at stampede disasters: every year people die because panic breaks out among a crowd in a constricted space and people start to operate on instinct instead of thought.