Literally that’s the stats - France top 1% income at 7.1k euro per month vs the US at 400k per year. And the top 10% in France is 44k (40k euros link) while in the US it’s some 170k (link)

When comparing upper middle class (1-10% income - doctors, lawyers, engineers, mid career business people), Americans earn much more than Europeans which is why it attracts talent from many of those countries. Median income is around the same you’re right. And being lower income is harder in the US with limited social programs.

They restrict working holiday visas to just a few countries so could be same here.

The 1% in France makes like 80k, the 1% in the US makes 400k. Less regulations more profits more competition for skilled workers.

Most countries have an identity as being a single people / culture and aren’t obsessed about being mylti-ethnic like the US. You’re taking your America centric views and applying it to the world when most of the world just doesn’t think that way.

Most countries aren’t multi-ethnic so most of the world doesn’t know how to deal with it. Chill out.