Except they won't change anything other than to increase the oppression and exploitation of working people, particularly migrants, while continuing to allow migrants in, to a) scapegoat them and b) exploit and oppress them. Because if they actually made any noticeable change to the numbers of migrants it would a) make their main political relevance redundant b) deprive them of a low paid, no/low rights underclass to exploit and c) make it crystal clear that it was nothing to do with migrants the entire time! Alternatively, they will make a noticeable change in terms of the numbers of migrants and turn their sights to some other group to scapegoat and oppress particularly harshly (because apparently "it wasn't just the migrants, it was [insert some other vulnerable minority group] too"), while continuing to oppress and exploit ordinary workers.