Yes if you bought your common stock and paid giant amounts of tax (via AMT[1]) on that purchase, you have put yourself into the position of losing all that money. But I wonder how many people have fallen for that trap? Of course the worse case would be RSUs where your granted (not optioned) the stock and are stuck paying the AMT without any ability to sell that granted stock at the time.

Everyone who is working for a Unicorn is, in theory, drawing a reasonable salary (unreasonable to those not in the tech sector apparently) so it isn't like your life savings that your living off of are now worthless (that did happen to folks in the dot com crash).

I have had the experience of having a basket of stock and options being "worth" over $12M at one date (when I could not do anything with it) and "worth" less than $80,000 when I could sell those shares on the market. But it didn't "bankrupt me" to "lose" over $11M dollars. Because all of the value is fictional until its actualized into cash. Just like every PowerBall ticket was "worth" $900M before they picked the balls, but after they picked them it was "worth" $0. Nobody should feel like they "lost" $900M because the lottery didn't pick your numbers. Just like you don't "lose" money because your common stock is worth less when you can sell it, than it was when it was optioned to you.

[1] The US "Alternative Minimum Tax" which computes your tax rate in a fantasy universe where you actually saw the gain on the security you just bought and pay that tax as if it were real.