Here's my problem.
> numerous
I dug into one such report that broke and apparently it was around 30 videos that they had found. When I checked Pornhub, I believe it currently had over 20,000 videos, and that was presumably after they'd been under quite a bit of scrutiny. IMO there is quite a mismatch in magnitude there.
Of course, there probably were other illicit videos, but there is no reason, in my opinion, to suggest that Pornhub had an unusually large problem. Unfortunately though, a lot of the videos like this that wind up undetected likely have been spreading through the Internet for several years going unnoticed simply because it doesn't look particularly different from any other pornography. As it turns out, at least certainly late teens look a lot like young adults.
This does create an unfortunate conundrum for anyone allowing user generated content that is pornographic. Even ignoring explicit abuse, teens are relentlessly horny and will upload inappropriate things to the Internet, or even try to sell it. Seriously short-sighted behavior, but you know... they're teenagers. We've all been there. It's not some alien condition.
I understand that people have extremely strong emotions about this and want a zero-tolerance stance, but it's not possible. If you allow adult content, you inevitably get some ideally-infinitesimal trickle of illicit content, probably often strictly by accident. Best you can do is try to find it and clean it up as effectively as possible.
I fully understand why it's treated like toxic waste, and I'm not trying to justify it, but no matter how despicable the crime is, you can't fully eliminate crime, it doesn't work that way. I think keeping "legitimate" pornography sites like Pornhub was actually likely slowing the amount of said toxic waste because Pornhub actually did moderate, clearly, whereas the back alleys that people are likely to fall back to are going to simply be less well-moderated by their nature. At the end of the day, most social media platforms proliferate a lot more CSAM than Pornhub has even if you estimate very generously.
In the Omegle shutdown letter, the founder notes that Omegle's content moderation resulted in some criminals going to prison. Pornhub's moderation has undoubtedly done the same.