It's really that simple. I also think Facebook is a net negative for humanity, but if I was willing to subject myself to leetcoding interviews and passed theirs, I'd work there in a heartbeat because they pay senior engineers with ~6+ years of experience about $400k as a baseline. Quite a bit more if you're particularly good, have competing offers and negotiate well. I have principles, but frankly I care about securing my and my family's future more than standing up for them. The same is probably true for most.