Ha no, of course I think that is impossible.

It's more like: we could build nicer, community-funded, sanely run social software, and alongside them we could support XMPP type features for hackers who are able to use them, or to interoperate with other alternative online communities that may be emerging.

Nah, I would favor a pitchfork-and-torches approach to Facebook and Twitter, the entire company behind it is so unlikely to change that a radical rebuild is required.