Do you get a US salary? What I’ve heard is that the same company pays much lower wages in the EU than in the US. (With the EU job coming with more non wage amenities like paid vacation, maternity leave, as discussed, and guaranteed healthcare and better public infrastructure.) But I have no personal data point.
levels.fyi contains salary information for comparison.
Take a Google L4 - $280K US, $190K UK, $160K DE.
But when you include the regulatory protections and benefits, the differences in living standards, etc. the US salary is probably still higher but these salaries are certainly nothing to balk at.
Yes, these numbers seem accurate. In my personal case, I could save a bit more (very roughly 20%?) in the US, but I've concluded that it wasn't worth it.
However, for higher levels (L6+), I think the difference becomes more important. Also, in US tech centers, there are many more opportunities than in Europe. If I were to lose my FAANG job, there would be no way I'd make the same amount of money in a different company in my country. On the other hand, being on a transfer visa in the US can make it hard to switch to a different company too.
In the end, there are pros and cons, and not a definite answer as to where it's best. It depends highly on individual circumstances.