A Cisco-like or Nvidia-like unicorn lifetime achievement is what everyone hopes for when they sign up for a Silicon Valley startup, but you can see the misery index rise when the stock is underwater and it make take years, a decade or more — or never — for those stock certificates to even be worth the paper you'd print them on. I've been at a number of startups where you can walk away after 2 or 5 years partially or fully vested and your options are not worth optioning.
Some people are indeed early Cisco millionaires. Many others only get in after the stock tumbles and are just really grinding away for salary.
Nvidia will also eventually find its natural limit. Joining Nvidia in 2024 is totally different than having joined it in 2014 when this article was written.
YMMV on this, widely.