Did he point out that Ireland has the same problem? Over 20% of the population of Ireland is not native born.
First-generation immigrants (foreign-born residents) make up approximately 15.4% of the United States population.
However... The figure for the Republic of Ireland (20% - 23%) includes people from Northern Ireland, Wales, Scotland, and England... because since Brexit, people moving to the Republic from those countries within the British Isles have been counted as foreigners. That accounts for about 5% of the post-2016 numbers.
Once you take the Brexit numbers into consideration, it’s actually 15-18% in Ireland compared to 15.4% in the USA. So in terms of scale, the ROI doesn’t exactly have THAT much bigger a problem.