This isn't a case of rampant puritanism, go to Pornhub (one of the milder purveyors) and tell me that most of their front-page content is a depiction of healthy sex between two loving adults.
The message becomes incredibly different. The very fact that you talk about "sexually charged content" while saying that the message would be the same with "breasts" vs "intercourse" is a demonstration of the cultural differences scrollaway mentioned. A lot of places "breasts" does not automatically imply anything sexually charged.
It matters, given that it is far less obvious to me whether or not your "updated" statement is true, depending on which specific age range we're talking about when you say "child" and how large a proportion of that age group needs to have seen any to justify generalising, and what "extreme amounts" are.
Go to [0] and tell me how that is a depiction of a healthy whatever. Also please describe how the paywall on porn sites would help poor 13 y.o. chaps not to see this.
LOL.
So you DO think this is a sexual content.
And the difference between 'other platforms' sexual content is the lack of an exposed genitals.
[0] should be sex depicted only between a loving adults? what about a non-loving adults who does that for fun and health?
[1] really?