There is neither emotion nor bias. A one lane narrow tunnel used for a single vehicle is a genuinely stupid idea. The reason loading and unloading times matter is that there is a limit to the vehicles that can be present physically in the system. There isn't infinite space at each station, and people represent obstacles on the track since people need to cross the track in two of the three stations.

Putting that aside, you can not infinitely parallelize the people streaming into the stations. Basically, we're looking at a leaky bucket buffering system here. In order to prevent the buffer from overflowing (too many people waiting) you need to move people into vehicles and through the tunnels fast enough. Likewise, to prevent the tunnels from being sub-optimally empty you need enough people buffered and waiting to join the queue.

The problem that TBC has is that they can do neither side of that. They can not physically move enough people into the station per fire code, and they can not move enough cars through the tunnels based simply on the speed and passenger capacity of each vehicle.

As I said elsewhere, why is it that the initial proposal was for 16 passenger shuttles at 155 MPH?

It's okay to be disappointed. Next year you'll be right back on board with me and we can both have a chuckle at the idea that TBC would extend single lane tunnels to the airport.