It's not ready yet. If they open for public now, ppl will be disappointed at how primitive and useless it is and leave before it starts. They're building up, so when it's good and ready, they can offer the world an app worth their time. But enen then, I doubt that it'll be as good as nostr, but it will have Jack and with good advertising(something nostr lacks), it will be a home like Twitter once was, you know before Elon.