This deal is effectively a one-time secondary market for existing investors to sell their stock. If I'm an early employee who has been wearing golden handcuffs for the last eight years, I'd probably accept a lower purchase price than "what they're worth" for the sake of that liquidity. That doesn't reflect upon Uber, or Uber's value. What you're saying might be true if this were a perfect market, but there's externalities in that market (like liquidity) which you're not considering.
> valuation = number of shares times last preferred price, but that’s a convenient fiction.
Fiction as it may be, it's the best instrument the public has to work out the value of a private company. Investors have access to internal numbers, apply due diligence (we assume, since it's their money), and give their best guess as to future returns. That doesn't mean we shouldn't scrutinise the valuation investors accept during a round, but let's not pretend it's not a good marker.
> $48B (or whatever it may be) is a spectacular success by any measure
I doubt existing investors would see it that way, if $21B were wiped off the valuation as reported.
> I’m not sure what you’re so defensive about
My apologies if that's the way it came across. I stand by the criticism I made of the article.