It’s simple really. If something as large as Facebook federates, you will never be able to know whether the users you are engaging with are actual people somewhere, and not just large language models.
It’s happening on reddit right now. The only value to this sort of website is engaging with actual people.
If I wanted to talk to a chatbot, I can already do that. Meta has proven again and again that it will manipulate it’s users with insidious content and moderation, and will knowingly harm users, such as by selling user data to foreign governments or deliberately fomenting depression and anxiety in its users, even kids.