The thing I would add is that Google's whole thing about "bringing your whole self to work" and providing food and amenities to keep you at the office as long as possible leads to some unfortunate effects: Many Googlers social circles are heavily filled with other Googlers, and a Googler may rely on Google for a lot more than just the paycheck.

If someone's spending say 14+ hours a day on a Google campus, leaving can be a lot harder than just "finding a new job".

Even some of those publicly protesting Google's behavior or pushing for a union will turn around and help promote their friends' products or encourage people publicly to apply to join Google.

So I'd point out they've successfully made it as hard as possible, socially, to quit.