People worrying about cultural displacement in europe need to crack open a history book and understand the movement of people is just how the world works. Its like the movement of air from different pressure areas. Most spanish people are actually a mix of moors and visigoths, other mediterranean people through history, and even celtic or germanic peoples who by and large displaced some earlier occupant of the iberian pennisula, who displaced some even earlier people, and so on and so forth until we get to whoever displaced the neanderthals. And all of this displacement involved assimilation too. Acting like migration should stop now would be like asking the wind to stop blowing or the tides to stop. Its like a natural law that people will go where theres better opportunities for them.