I didn't say anything about USB? If you're referring to upthread wanting RAM to be standardised like USB (not standardised on something like USB), I took that to mean backwards compatible slots. (And maybe handicapped forwards compatibility, though why would you.) M.2/PCIe is this way.
They obviously did not mean not literal USB, just a standardized connector across DRAM versions/speeds.
Yeah, sure but... if it's real fast, lets connect SSDs to it and have real fast swap. Whatever it is will be limited to the bus speed. And that's gonna be silly compared to RAM speed.