That isn’t what Discourse is. Discourse is a discussion forum. From the team: “We’re on a ten year mission to improve the Internet with free, open-source discussion software that raises the level of discourse for the entire world.” (emphasis mine). What you seem to be looking for is a social media or personal blog system. I’d suggest using SSO to integrate an existing system into Discourse, rather than turn Discourse into something it is not.
No argument that Facebook does things well, but Discourse isn’t trying to make a social media platform - that’s why it doesn’t make a lot of sense to copy what they do.