You know this? As far as I can tell, it's still possible to find weird little sub-sub-sub-culture groups on the internet if you actually want to, and curious kids can do it. Maybe most kids aren't, but I don't think there was ever a time when most kids were exploring the full possibilities of the internet either. Put another way, maybe the fraction of internet-using kids doing stuff we'd think is cool was higher back in the day, but I think the fraction of kids in general doing stuff we'd think is cooler is higher now.
I might as well say that I know that this isn't true because they don't know what the Internet could be... all they know is the centralized cloud.