I have worked around/with many many Mexicans; both legal and illegal; and most were never planning on staying here forever. Lot of them still sent money home to wife/Sancho (if you know, you know

; and had a specific goal; start a small business, build a house; basically the American dream, exported back home. Now, in my experience, the 2nd generation, born here, are a different group, culturally and work ethics. I've also worked around a pretty good number of eastern Europeans, who generally were here for good; some Nigereans, some Indians, Caribbeans;
I think a big change from earlier immigrants, is, it is Much easier to keep a connection with the old country (if they want). It used to be a one way trip; never hear from the family/friends in the old world; now, it's a $250 plane ticket home for 3 weeks.
There is also a large Myth in other parts of the world that the US is the land of milk and honey. Come here, make 10 years of income in a year and go home rich. Then they get hit with the reality of barely making it. If you go to many parts of the world, all they see of the US is TV, movies, and YouTube stars, who have 3 lambos, a beach mansion, and they think that is the norm.