This view seems somewhat reductionist, no? I don't work at FB and never have, but I could easily see a case for working on projects that contribute back to the developer community (e.g. React). These wouldn't be directly related to user tracking/privacy violations and they might be selling their souls, but are contributing something useful to the world. In this case, what do you think would step up to fill the void in OSS, and what do you think is the best move for one of those developers?