As an IPO this sounds similar to most biotech/pharma startups. These companies routinely IPO in the $50-100 million range when all they have is a patent, some promising data but no approved clinical trials and no business.
Of course it's different because there's a clear post-IPO acquisition market for biotechs. Not quite as clear who would buy Hyperloop if it's proven to work...
Meh. If I give you $100 for a 1*10^-6% stake in your company with a guarantee that you will pay me back at least $100 before honoring any other debts or issue, are you really a ten billion dollar startup?
It's most entertaining to subtract any preference off the top of the valuation. I wish it became a trend. Particularly for preferences with multipliers!
Of course it's different because there's a clear post-IPO acquisition market for biotechs. Not quite as clear who would buy Hyperloop if it's proven to work...