"Then there’s the Prestige. Facebook gets a lot of blame in media lately, but in everyday life it’s still very prestigious place to be working at. Getting a mortgage or a car loan is easy, saying you work for Facebook gets you on the fast line."
That's the money quote, this person is only thinking about themself and really doesn't consider how their work impacts society or what company they're helping as a priority issue at all. I don't know why people like this are the way they are, it seems to border on sociopathy or greed or something to me ("screw you guys, I got mine.") At times they must have just buried their head in the sand over all the Facebook scandals including helping a freaking genocide. It's crazy, and reminds me a little of "American Psycho" to be honest.
I don't think he is morally at any fault.
Here's another way of looking at it: Fb is so damn big, there's no reason them looking bad to the public should condemn every software developer on their payroll.
So no ethical responsibility? I strongly disagree. They could've quit at any time and found dozens of jobs elsewhere with a resume like that. Judging by the post they did after nearly a decade, and only because purely selfish reasons. I was maybe a bit harsh, but come on..