I have 6 weeks of vacation a year (2 years out of uni) and 240 days of paid (75% of normal pay) parental leave (480 days in total for both parents). How's your vacation and parental leave in comparison?
But my larger point stands: the average cost per worker for those benefits is only maybe 10% higher than the cost in the US for our reduced benefits. So why are salaries 50% lower?
in US 6 weeks of paid vacation is still rare in professionals. 3 is common. So you're using 3-6 while in europe there is guaranteed 6. This is apples and oranges.
Besides: this is in addition to the sick time. Sick time is paid and you don't use vacation time for that in europe. How is that in US? Can you get additional 4 weeks paid sick time? Can you get 8?
Then in addition you have this perks in US as long as you work as professional in top companies. While the real difference in terms of health care is after this work. Last I check, average age at FANG is below 30 yrs in USA! Wow! So imagine you're 45, you dont work at google/etc: then at low impact events or maybe even medium events if you dont have family healthcare is comparable (your savings cover it). But at high cost/high impact situations or medium ones if you have full family, you're not covered (add to this highest in the western world cost of healthcare in US). While it's state funded in europe also at the high cost level (read cancer therapies and all the things like). This is big difference for last 40 years of live.
And then you have mentioned maternity: that alone (and most of people have families in any place of world) from family perspective is a huge difference financially AND child development.
p.s. and there is cost of living. in US alone you can easily have it in SanFran at 1.77x of US average - you can imagine how it scale to the other parts of world? Sauce: https://www.wolframalpha.com/input/?i=cost+of+living+index+S...
There are simply much more well funded companies in the US, desperate to find good candidates, thus driving up salaries.
What's also interesting to consider is that developers here seems to be fine with earning close to non tech jobs employees. You can do really well in many industry sectors. As a bus driver in Germany you can earn $31,435 which already buys you an ok level of living.