not only is it half closed source it hardly works properly either, has the same key-sharing problem as simplex (you can't have the same identifier on separate installations) and the actual "holepunch" technology isn't always effective at getting results

in all seriousness, i don't know what the fuck they bother with this nonsense for, you can use the IPFS protocol to enable bidirectional peer to peer connections, including internet connected nodes performing rendezvous for your peers

and not only that, it got abandoned because Tor changed the API so much it broke it but there was a p2p chat that used tor hidden services called Torchat... i'm not sure, i don't think anyone has bothered to try and get that working again but literally can use tor hidden service identifiers as your public keys to connect to you when you are online

all of them have a problem of async messaging though, something that Nostr can solve if some devs get their heads out of their arses and start putting full relays inside clients and building desktop clients with backend services that run as your inbox/outbox

all possible, all can be done with the tech, yet somehow nobody is actually doing any of it. retarded.