I'd describe it like giving everyone a gun. In theory it's just a tool that can be used with good intentions and there should be no problem. In practice, people are fucking idiots...

If most people had the intelligence and self control of a mature, confident adult, Social Media would just be a great tool to communicate quickly with each other. If companies were focused mostly on keeping their profits steady and their userbase content, Social Media would be a healthily moderated and open area for sharing ideas. Instead it's a hotbed of bickering, flesh selling, virtue spirals, hate and the forming of social groups in order to attack other social groups, run by companies who are focused on addiction, feedback loops, constant growth and milking the worst of humanity for profit.

It's still a young technology. These may be the teething stages of it. In time it might become a healthy place, once the little social wars that need to be fought with it before people start to see how pointless that is are over... For now? I wouldn't let a kid near it, that's for sure.