In Mexico City's Museo Nacional de Antropologia, a large area is devoted to showing how various subgroups of the Mexican population have preserved their customs and way of life. The focus is on those of predominantly indigenous descent.
Many of these displays end with a note about the effects of ongoing, increasing, out-migration. Here's most of one:
And here is yet another such anthropological description of social havoc.
What looks to some in the United States like an invasion looks to many in Mexico like the death of ancient ways of life.