> This is unfortunately true. I do know people who aren't happy in their job (maybe not to the point of actively hating it), but stick around because of their golden handcuffs.

For anyone "stuck" in this situation, recruiters from the other FAANGs you don't currently work at will try to match unvested shares in their offer. It always pays to interview once a year or so to see what the current offers are like, and it's fun to try out the other microkitchens. Well, until 2020 I guess.