This is gold. Not so much for the comments on Google, as for the comments on what being fearless does to you. But I've also experienced that you need to couple being fearless with having some superior or even unique skills to maximise satisfaction.
"When you suddenly have enough money in the bank so that you can quit when ever you want, you lose your fear of losing your job and trying to find another. And not having that fear to hold you back, can be tremendously empowering."
My take on this is that (if you are a good engineer) you can just choose to be fearless anyway and trust you'll get a job whenever you want one. Life is too short to skulk around in fear of what some random middle manager thinks about you. This doesn't mean that you should go around rubbing people the wrong way (you shouldn't) or that you shouldn't be trying to make your FU money (you should).
But I've seen many many talented devs twist themselves in knots, trying to please their managers' unreasonable demands, and otherwise live a life of cringing fear or quiet desperation, just out of fear of being fired/demoted/whatever. This is particularly true in India, where hierarchical power structures are more pronounced than in the USA. and losing a job has more of a social cost.
"Nearly every single person I know who has 'retired' it really meant they stopped reporting to someone else and instead invested their time and energy into things they were passionate about and could make a big impact on."
Gold. I am only semi-"retired" (I have money in the bank, I don't really have FU money. Any day now ;)) and I am nowhere as talented as Google's top 20 employees, but this is true ime.
I was always fairly "fearless", so didn't have to work on that bit. But I did have to consciously choose never to work on uninteresting/boring things or with boring/uninteresting people.
(I am aware that most people in the world don't have that choice - all the more reason that people who do have such a choice should probably exercise it)
After being ground down after a decade of working on outsourced enterprise software -and it did take some grinding, some of us are good at deceiving ourselves - I decided I would never ever work on meaningless (to me) things again or with uninteresting people.
It paid off in spades for me. I now work on interesting machine learning projects, and have more interesting work offered to me than I can complete in a lifetime. I work much harder than in my salaried 'coding body' days, but the work is challenging and feeds my soul.
"making things happen is a powerful drug."
A very very addictive one, and you don't really need to be part of a large organization to partake of it. There are many people working quietly in many areas on very ambitious projects, with little fanfare - there is a large world outside the valley (and outside software). Perhaps the drug is too addictive, but that is the subject of a different post.