It failed to gain traction, and Mozilla eventually pulled the plug.
Persona had many advantages over the Web3 vision described in this article. It was painless for a new user to create an account, because Mozilla provided a default identity server. It was easy for a website owner to set up, because Mozilla provided a JavaScript shim that worked on any browser. And it didn't rely on a wasteful and slow distributed ledger.
Despite these advantages, Persona failed. I don't see how a blockchain-based approach, with so many disadvantages compared to Persona, could possibly succeed outside of the blockchain enthusiast community. And, on a technical level, a federated approach seems innumerably simpler and less wasteful than a blockchain-based approach.