Europeans hate moving. They're not like the European diaspora, they will live within a days drive of Switzerland, all their life, and never even consider the concept of trying to make a life there to earn 2-5x as much.
Everyone hates moving if their lives are good enough. They generally only move because they think their environment has structural problems that can't be solved within, say, 5 years. For example: bad healthcare, generalized low level corruption, bad infrastructure, bad air quality, no opportunities, etc.
Americans are probably the only developed people that will move en masse just to make a bit more money, and even that's because there's no language barrier and hardly any cultural barrier. Plus it comes with downsides, no support network in the new place, if you're out of a job... things can become extremely sketchy.
Americans don't move en masse. They move as individuals. Lots of people in the UK move to London to make money. Move to the capital, make your pile, leave at 50 and buy a big house.
Moving in Europe is not like moving in the US. Language is the big one ofc, but the cultures are vastly different compared to US states. That doesn't mean it not worth it, but it adds a layer of friction.
