A tunnel is a terrible place to have a train, on account of needing enough space around it to pass the air, else you enjoy a pressure bubble at the front of the train. But increasing the cross section of a vacuum tube is a non-negligible nerf to the effectiveness of the vacuum pumps, causing similar drag anyway.

This leads me to believe that even if the technology works perfectly, the numbers alone won't allow for the performance that was promised, unless at extraordinary expense in running the pumps.

Edit: Also, if there are any magnets at all on the car, or along the length of the tunnel, induction is going to be a surprise drag.