I can imagine one - maintaining adversarial interop with proprietary systems. Like a self-adjusting connector for Facebook for some multi-protocol chat client. Or if there's going to be a Usenet-like system with global identities of users and posts, a mapping of Facebook to that. Siloed services don't expose identifiers and are not indexed, but that's with our current possibilities. People do use them and do know with whom they are interacting, so it's possible to make an AI-assisted scraper that would expose Facebook like a newsgroup to that.

Ah. Profitable. I dunno.