Do you have a source for that? I work for a large international company with engineering teams in many countries including European and American ones, and the workers in Europe generally make a bit more than the ones over here. Small sample size, but I feel like you are comparing a small subset of workers (Developers in SF/NYC) to a large one (Developers in all of Europe).

I'm European, and have seen numerous anecdotal numbers of salaries in US companies, and it seems much higher than what I'd expect to get here.

I understand your point of view, but I would point out the other side of the coin.

People who are not able to give their whole lives up to their employer's demands, for any number of reasons, are less able to work in tech in the USA - they're not good value with even if they have reasonable human needs. This contributes to a very unequal culture in the industry.

(Even if people on this forum might generally benefit from that)

It's almost as if people with different cultures vote to create the kind of society they want to live in. :)