You can try, but you’ll be teaching to deaf ears until they have seen enough to understand what the hell you’re talking about.
Kinda like teaching kids about heroin or cocaine.
They should also learn not talking to strangers by putting their lives at danger.
There have been priests that taught sex education using your logic.
There have been priests that taught sex education using your logic.
The kids who “learn” from such priests are kids who haven’t been exposed to proper sex ed. Generally, they’ve learned that sex is something that should be concealed. It’s a secret that the kid isn’t supposed to know about, so of course they don’t tell anyone about it, because they know how to stay out of trouble.
Gatekeeping the Internet works the same way. If you’re going to do that, you might as well download the sex offender registry and invite them all to the kid’s birthday party.