I really can't speak for Poland specifically, but if someone is leaving one country for another, it shouldn't be an issue. And it wouldn't be if that person were not simply making room for another. The industrial countries had solved the problem of expanding populations, and some were on the decline.
             Things were looking up until the mass migration began.

             More troubling to folks who made personal sacrafices to recognize the problem and to take it upon themselves to do something about it, all their efforts have gone out the window, along with their heritage in many cases.