I suspect that depends on subtle phrasing.
If for the sake of argument I presuppose that film classification ratings are necessary to protect children’s mental health, then the un-filtered contents of shock sites and porn sites will have had an impact even in the early years of the internet.
However, the early years of the internet simply had a much smaller proportion of kids online to experience this.
No*, however the point is valid: the internet overall is indeed unfiltered far beyond what is allowed in even the highest cinematic ratings.
* I avoided such things, however I do know the low end of what they can be, and had in mind 2girls1cup which I understand to be criminal "extreme porn" by UK standards, though have never actually seen it.