I don't think it really is, because the proposal was a comically unserious one designed to generate interest in the underlying technology. The route proposed in the paper as a supposed alternative to HSR which has termini outside of the immediate area of the population centers which it notionally connects would never be useful and will never get built.

OTOH, the interest the technology has drawn from that splashy initial PR campaign means enough people are working to develop it that that, if anything like it is viable, one or more commercially-viable variants will likely be ready for Musk's Mars colonies.

> On paper, it's better than the high-speed rail in every way. Cheaper, faster and with less pollution.

Its only "cheaper" because the proposal both made unrealistic assumptions about real estate costs and avoided much of the real estate costs by not terminating any place with useful transit access to the population centers at either terminus.

Unlike HSR, which not only terminates near the population centers, but includes as part of the same project improvements in the local connecting transit systems.

The proposed Hyperloop route was the high-tech version of a bridge-to-nowhere.

Outside of governmental regulations, the market is what determines progress and there isn't much push by consumers for environmental impacts. They just want cheap and reliable transit. Price also wins over speed (and it's been show things like wifi have a greater effect on travel comfort than speed).

Unless you cut down the travel time significantly, it just doesn't matter. And at those speeds there are more engineering, operational and logistical costs that increase the ticket price so the value is reduced further. I also don't see how the engineering for a pioneering vactrain concept will somehow be cheaper than existing understood infrastructure.

Unless you can charge $50 and get from LA to SF in 30 mins while building the entire thing for just a few billion, this won't work.