I always kinda liked this one of a motorcycle engine with one end cut off. You can see how the valves work, and how they are designed to rotate under load, to even out the valve seat wear.
"The government" is virtually the only entity that has ever taken any interest in space flight. The cumulative government investment in space research, development, and operations is orders of magnitude higher than the the cumulative private investment, and even today in the supposed golden age of private spaceflight more than 80% of the money is coming from taxpayers.
The analysis conflicts with personal recollection. It seems to show leaving SF at 4pm and being able to get to roughly central Mountain View in an hour. Google Maps says that if I leave today at 4pm, that trip takes "typically 1h - 1h50m" which in my experience is about right. One hour is a good outcome, not a normal one. In a car, at rush hour, sometimes it could take an hour to go four blocks down Battery Street in SF.
Also, of course, the article has neglected other modes than cars. If you leave on a rush hour Acela train from Boston you'll be in Providence in 33 minutes, well outside even their 10pm driving radius for Boston.
Lost me at "And lots of people learned that monorepos are really painful, because past a certain size they just stop scaling." Plenty of counterexamples of monorepo projects much larger than Linux kernel.