Not everyone is happy to move around in the world just to earn more money. I can’t imagine that a lot of people from Europe would just move to other countries or even continents, just to make more money. So, I don’t expect a “brain drain” to happen anytime soon.
That being said, I’m sure the salaries in Europe aren’t so great, but that goes for many things and other sectors definitely have it worse than tech workers (e.g. healthcare workers).
And it sounds like you could try working for smaller companies that are more agile and don’t have such annoying management issues! (At least in Germany they also tend to pay better or equally well as big corporations.)