Well my intuition says the opposite and that those numbers seem to track with my expectations. A large bulk of users likely never sign up for PH, making it har

Well my intuition says the opposite and that those numbers seem to track with my expectations. A large bulk of users likely never sign up for PH, making it harder to vet individuals to make sure they wont report the content. People show up with pretty much one thing in mind when going to PH and it's not really to interact with communities. Facebook has so much reach and such a large userbase that it's harder to moderate, and it's used for exactly what these groups want to do. If we were only talking about close to 18 yo CSAM, sure that I could believe might be something that is more common on PH. But when looking at the entirety of CSAM, I just find it hard to believe that people would risk uploading a video that clearly has a child in it to a service that actively moderates video content primarily to a community that, en masse, doesn't like the content. There could be some tabulation issues, but I find it hard to believe it's so poorly counted that it would make up a meaningful difference between the two numbers provided.