> Internet psychoanalysis based on "telltale signs" is just seeing what you want to see especially if you're responding to a perceived personal slight. The people telling you they're having the time of their life also might be projecting to try not to feel bad for their life choices.

Not really. I've worked at a FANG for quite a few years and I can tell you from my own personal experience that in many ways it was the best job I ever had. The misery imagined by OP has no bearing in reality, and screams projection. I see it a lot, sadly. People are desperate to get in and when they don't then they resort to shit-talking things to try to make themselves feel better.