[benterix]

> You could, for reasons I never entirely understood, make so much more money doing the same job in the US than anywhere else. [...] e.g. Europe.

It really, really depends. First, not every SE works at top companies, and even there the salary can vary much. Second, in Europe you can often choose your contract type - if you choose a permanent role, you surely earn less, but at the same time enjoy the level of social security your counterparts at FAANG can dream of. If you choose to be a contractor, the median will still be lower than in the US, but not that lower.