Briar can be banned, but for now it can't really be blocked though. It's supposed to work in case the infrastructures are down by design. So it can also work

Briar can be banned, but for now it can't really be blocked though. It's supposed to work in case the infrastructures are down by design. So it can also work locally, meaning 2 Briar users can meet, and share messages from 1000 other users, and go on their way to propagate the update, without going trough the internet. Now of course you can always enforce the ban, not through blocking, but through detection and punishment. However I doubt you want to spend that much resources for a single app.