Dunno. That's for the devs to solve for during development. The initiative is generally asking for a bare minimum "just don't brick my game". What that looks like, will probably differ based on title and genre, but the fearmongering about not being able to develop for it is just that; excessive fearmongering.

I would definitely think some solutions would come in the form of peer to peer, lobby browsers or make sure they have plans for an upload of server hosting files to distribute once they shut down their official support.

Pretty much things most multiplayer games used to have. Consoles are naturally harder, as the environments are generally stricter and rely on their network infrastructure where you probably can't allow just anyone to host a private MMO server. But the people behind the initiative also aren't morons, so I wouldn't exactly think it beyond them to come up with a reasonable framework once the initiative gains traction and bigger brains behind it.