There’s no way of knowing the age of CR readers, but kind of like the “grandma rule” if its fit to be read in the CR (or using terms that are pareve enough to satisfy the mods) then I think if a child has internet access, they will be safe here.
No guarantees about what happens in other sites, but the CR is a safe haven.
My personal hunch? That other poster was just trolling or campaigning. That’s why he was sent packing.