We already have a 700mph metal tube in a partial vacuum transport solution: passenger jets. Arguably, the main inefficiency there is that airports are located

We already have a 700mph metal tube in a partial vacuum transport solution: passenger jets. Arguably, the main inefficiency there is that airports are located far from city centers and involve large amounts of time and financial friction. So where's the startup to make downtown SF -> SFO -> the door of the plane take 30 minutes instead of 2 hours?