I think a more accurate statement is that the internet was never safe for children, but online content was never monetized and targeted to various audiences for nefarious purposes the way that it is now (including towards children).

I would also make a tangential argument that interacting with the internet used to foster a degree of technical ability, critical thinking, and reading comprehension that just isn’t necessary when “going online” can just mean downloading an app and mindlessly scrolling through an endless short-form video feed. On a macro level, today’s internet is dumbing kids down, while yesterday’s internet required (or at least encouraged) some understanding of how systems and technologies work.