How the hell would kids today have coped with the internet 20 years ago. The answer is same as kids 20 years ago did, just fine.
Now the constant sharing of dead bodies, murdered kids, etc - yes that could be traumatic. Someone’s arse?
Bad shit happens in this world. if you don't think you can protect your kids from it forever, you might want to think about teaching them how to protect themselves.
"You're going to see pretty bodies and ugly bodies. Sometimes even broken and misformed bodies. The people in those bodies are a lot like you, usually, even when they look quite different."
And arguably they SHOULD be exposed to this content if we want our society to be versed enough to just maybe take steps to fight it.