I've not read anyone claiming that the Hyperloop is technologically infeasible. It re-uses a lot of known concepts and will likely work.<p>Most of the concerns I've read are about construction costs, safety (e.g. escaping a stuck hyperloop train), failure modes (e.g. what if the tunnel suddenly floods with air from e.g. an earthquake), practicality (the Hyperloop trains as envisioned don't support wheelchair access, and don't have toilets), and similar civil engineering challenges.<p>If a hyperloop were designed to transport cargo/mail then I think that would "solve" most of the perceived problems (except maybe construction cost). But transporting people adds a whole new vector of complexity to the concept.<p>Again the core concepts of the hyperloop are likely sound. The thing would work if we built it. But it doesn't mean it will ever be built and even if it is, that any passengers will ever be able to utilise it commercially.
Why spend billions (perhaps trillions) of dollars to get a pod full of people to fly through a tube when we already have technologies to fly pods full of people through the air at the same or higher speeds?<p>Cheaper and greener air travel will be the solution to this problem in our lifetimes.
The Hyperloop would be a nightmare to inspect in a natural disaster. I know how difficult it is now to check on trains now, can't imagine this being fun.