As for liability, the Ninth Circuit in Mavrix v LiveJournal held that if an agent of a user-content-hosting ISP (social media) has the means and opportunity to moderate, they also have the means and opportunity to interdict reasonably known copyright violations, and failure to act on those would jeopardise their DMCA Safe Harbour.
And there’s a lot of registered copyright holders that will 100% line up to be a creditor on statutory damages.