> - 2-3x speed of bullet trains. Can change the way we perceive geographic distance.
> - Cost isn't as much of a concern because a national hyperloop network would create a lot more value than a bullet train equivalent.
High speed brings with it some pretty severe problems. The most well-known is curve geometry: curve radii scale with the square of velocity. Transition track (how long the "S" of a S bend needs to be) scales with the cube. But it's not the only issue. Also scaling quadratically with speed is energy consumption and stopping distance. Speed only gives you a linear improvement in time, so things like capacity decreases [1] and stop penalties are only linear.
But the difficulty you face is switches. Here, you have curve radii constraints, which means your problems are in the quadratic issue. I've never seen any depiction of a hyperloop switch [2], but I imagine it's going to be more in the vein of move the entire tube than just swap a point. In any case, a high-speed switch capable of being traversed at 200 km/h is... 164m long. To go 1000 km/h would require it to be 4.1km. That means it will take a vehicle at least 14.76s to traverse it. So you can't schedule vehicles any tighter than that, but for safety reasons, you want the following vehicle to be able to come to a complete stop in case the switch breaks down before it can complete moving--which is going to slow you down to minutes between vehicles [3].
With these constraints, you might think people would be trying to design high-capacity vehicles, competing with the ~1000 you can stick on a normal trainset. But the design is more akin to a small airplane with the wings and tail cut off, fitting maybe a few dozen people per pod. Actually, the more you look at the designs, the more you see airport-style operational motifs sinking in. It starts to look a lot more like a long chain of point-to-point links, with the capacity issue of airplanes, but the infrastructural cost of railroads. Even the modelling seems to basically assume that people will treat hyperloops as airplanes.
[1] Yes, making a train network higher speed decreases its total throughput.
[2] A telling sign in itself.
[3] The highest capacity metro systems today can manage to schedule 45 trains per hour, and most systems are typically about 25 trains per hour. I believe the highest capacity HSR line is 6 trains per hour.