The only way this will happen in the US is if Congress requires it. The vast majority of the infrastructure to make it happen already exists. Especially with the large custodial banks offering “white label” services.
The Federal Reserve could go ahead and do exactly this without Congress's help. You know, actually serve the people and come up with a solution to the changing times like they did with ACH back in the 1970s. That's probably asking too much of our leaders though.