Also, under US law, ignorance is not a defense in both civil and criminal court. It does not matter if you did not know it was illegal, it does not matter if you did not know it was happening, if you provide an avenue and forum for illegal activity you are culpable at minimum. The corporate shield will prevent any criminal charges against individuals, unfortunately, but the civil liability is pretty evident. It occurred on their platform which means that they did not take sufficient steps to prevent or discourage the practice in the first place. It should not have been a thing that was present to report or react to in the first place. It falls into the same vein as doing background checks and personality evaluations on prospective teachers and daycare workers. Doing 0 checks to validate that these people are not a danger and then claiming ignorance when they touch children in the broom closet is a nonstarter too.