There's lots of information the web that a child couldn't access before the Internet. Harmful issues like sniffing paint, how to make weapons and bombs, communication with pedophiles and on and on.
Before the Internet any information a child had access to came from their local community and local standards were easy to control. If a newsstand was selling harmful information, they would be shut down either by the law or public outrage.
The basic difference is, children had no contacts beyond the city limits back then while the Internet has no borders and almost no controls on the content.
