Oh, porn definitely is an extremely old thing.
Pompei is remarkable in that aspect. Not only for the porn [1] preserved by the eruption, but also for the (some explicit) graffiti [2] [3] [4] [5]. It seems their perception and use too have evolved over time. And that "x was here" truly is timeless.
[1]: https://blainebonham.com/the-brothels-of-pompeii-may-i-see-a...
[2]: https://www.theatlantic.com/technology/archive/2016/03/adrie...
[3]: https://kashgar.com.au/blogs/history/the-bawdy-graffiti-of-p...
[4]: https://www.wondriumdaily.com/writing-on-the-wall-decoding-t...
Either way I think social media platforms should tune their filters to each society they operate in.