@Eaglelord17 is correct its happening very young now. My daughter is 10 and she is the out sider without a a cell phone. And my wife could spend a day telling you stories of what kids in her primary school are getting caught doing and sending to each other.
We need sex ed and net literacy from about kindergarten on now, most of this should be done by parents. Yup that's what we have willingly done to our children for our "freedoms". We have given up common decency and the protection of innocence for the sake of some smut dealers right to produce graphic material and slam it in our faces.
Porn used to be a scummy mag that someone stole from their father or uncle, or a the lingerie section of the Sears catalogue, now its TikTok, IG, Snap Chat, twitter ect ect. If you want the real stuff a simple Google search will scratch your itch.
Parents who aren't paying attention + companies and organizations who exist only for wealth creation while adding nothing to the overall society + the Gov enshrining their rights via freedom of expression = The truest sign of decay for our society.