A cynical person might say it’s deliberate.
This is the best explanation of why Western countries are being overrun:
It’s by Auron MacIntyre, a writer for Breitbart.
In a nutshell the super-wealthy need to get rid of the kulaks (that’s us), with whom they compete economically, by using the pincer strategy, leveraging the poor. However that doesn’t work too well if the poor share the same heritage and traditions as the kulaks.
So what to do?
Import a dependent client class that shares no traditions and loyalties with the kulaks! Problem solved (until the client group kills the elites and takes their wealth).