I think it boils down to the simple fact that policing user-generated content is completely possible, it just requires identity verification, which is a very unpopular but completely effective idea. Almost like we rediscovered, for the internet, the same problems that need identity in other areas of life.
I think you will also see a push for it in the years ahead. Not necessarily because of some crazy new secret scheme, but because robots will be smart enough to beat most CAPTCHAs or other techniques, and AI will be too convincing, causing websites to be overrun. Reddit is already estimated to be somewhere between 20% and 40% robots. Reddit was also caught with their pants down by a study recently, with an AI robot on r/changemymind racking up ridiculous amounts of karma undetected.