Social media is nothing like books. It's also nothing like eBooks, Wikipedia, regular discussion forums, telephones, etc. Modern social media has some completely novel characteristics that are responsible for its damaging effects on mental health.
- It's optimized to "maximize engagement," which is code for making it addictive. When anyone says engagement in our industry it's usually a euphemism for addiction.
- It does this by sorting content to present "engaging" content first, which due to how humans' brains are wired tends to be content that is emotionally triggering in some way.
- It's primarily consumed on a device that people carry with you and that has an interface that makes infinite scrolling easy, replicating the basic design of a slot machine.
There were dumb panics about books, but citing those to dismiss concerns over social media is intellectually lazy. They are very, very different things. Books don't watch you while you read them and fine-tune their content in real time to maximize the amount of time you spend reading them.