#3 "request deletion of all of their content by the admin" is a problem for message threads where a user's content is critical to the rest of the user's messages in that thread. They should not have the right to ruin other people's contributions if their post is important or replied to. What I would suggest is that they have the right to remove their NAME from posted content, not the content itself, in order to make their content anonymous. At our 'lesson' content site, we view all posts as...

That item is a "request" by the member for the admin to delete their content. You can refuse to delete their content, if you feel it's within your rights. We're just providing the mechanism that will support compliance with GDPR; what you choose to do with it is your decision as the owner/admin. Unfortunately, when technological solutions are legislated, they don't always think of the consequences for all scenarios. Sadly, online communities were not really given deep consideration when...