Theoretically this is true, but in practice it's not. Most p2p services rely on the global internet in some way. The BitTorrent DHT, for example, is unlikely so self-heal in the event of a completely inaccessible global internet.
Things like HolePunch have a lot of potential here, but you'd need an Iran-only DHT, and it's just not deployed at scale.
Things like HolePunch have a lot of potential here, but you'd need an Iran-only DHT, and it's just not deployed at scale.