Somehow my son grew up just fine in this environment and we are now living through our daughter growing up, but her interests in this area do not seem to go that way and her phone used to be completely locked down, which I had to relax to let her do more stuff on her phone but I think we keep a pretty tight watch on it... Also, I deviously refuse to upgrade her old and super slow phone under pretenses that it is super ruggedized and iPhones cannot compare...
I wonder at what point it turned though? I suspect that your son is a little bit older. But the neighbours kid (now 16) for example was in a school whatsapp group with boys and girls when he was 11, sending dick and pussy pics to each other.
:D