What's missing from these debates is optionality. A company pays you not only what it takes for you to do the job, but also their perceptions of your options. Two people working the same job on-site at the same company can have a substantial pay difference even without negotiation because one is self-taught and has only high school while another has a master's degree from Stanford. Yes, the former's competent and shows drive and ambition and that's nice. The company just scored a dark horse. But the company also knows the former employee (likely) isn't as aggressively courted by other companies which can pay well, so they feel they can pay that person less.
If you're the only person in the world who can do what Facebook really needs done, they'll pay you $1M+ to do it from anywhere in the world.
If you're the only person in the world who can do what Facebook really needs done, they'll pay you $1M+ to do it from anywhere in the world.