I see a lot of HNers lamenting the loss of persona. The code's available, so what's the major issue preventing its continued use? Is it the use of de facto add

I see a lot of HNers lamenting the loss of persona. The code's available, so what's the major issue preventing its continued use? Is it the use of de facto addresses, like the fallback login.persona.org? Couldn't that be mitigated by either establishing a new de facto standard (either commercial or community run), or by adding a fallback field to the protocol?