You're right that these are not the only place that people can write software and that many of us have recognized for a very long while that these are noxious places to write software, or that they were eventually going to become so.

Billion dollar FAANGs and their smaller, cargo culting, shadows represent a certain sector with a certain work atmosphere, much as game development companies and hedge/trading firms do. 15 years ago, during the ascent of Facebook and Google, this atmosphere was different than it is now -- innovative and luxurious and inviting -- and some people still look see them through the lens of the past, but they're much larger machines now, with different priorities and incentive structures, and as the author notes, those are mostly not aligned with sustainable, satisfying, or healthy environments for most of the engineers who've found themselves inside of them.

Like finance, they pay extremely well, and like games, they can make you feel like you're part of something you can brag about at a dinner party, but also like both, they have little concern about chewing you up for as long as you're willing to bear it.