Is Facebook a publisher?
The truth of the matter is that Facebook is now a publisher and as such it can be sued, at least in the UK, for defamation. In 2019 intentionally or not, Facebook admitted, for the first time during a court hearing, that it was in fact a publisher rather than simply a platform for sharing pictures of new born babies and funny cats. - Yair Cohen, Social Media Lawyer
And when a social media site is a publisher, and not a platform, it is responsible for its contents; it can make editorial decisions particularly on whether to ban or suspend users from its platform. Useful to know.