Comment by loandbehold

Books can also be harmful if abused. They can be used excessively as escapism. They can contain dangerous harmful messages and manipulation. They can be addictive just like anything else can. Content matters a lot, and anything that makes delivering content easy comes with the risk that it will deliver something harmful. Books, TV, and social media have all been used intentionally to spread harm and encourage addiction. Most adults have at least some chance of protecting themselves, but children don't have those defenses developed.

It's a good idea to be aware of every form of media children consume.

That's still consumption of images rather than participation in reality. Kids can absolutely read in excess as a form of escapism. Books are easier than dealing with real life when someone else does the thinking and problem solving for you. Certainly great for learning in moderation but you won't learn interpersonal skills or how to ride a bike just by reading about them.

I don't think there was. But even if so, there was a time people used to think the same about drinking antifreeze, too.