There's no reason for it to advance - we have good alternatives, and there's no benefit that this kind of system brings that is worth the massive extra cost (wh

There's no reason for it to advance - we have good alternatives, and there's no benefit that this kind of system brings that is worth the massive extra cost (which mostly can't be solved - it's the massive amount of material required for the vacuum chamber and the massive amount of energy required to pump down and maintain the pressure. High-speed rail would be extremely cheap in comparison).