It was just an exaggeration surely. He meant that "lots" of people want to come to the US. People exaggerate all the time, eg
"It'll be the end of the world if I get a cold at Christmas!"
"My mother is going to kill me when I get home!"
"Everyone in Poland wants to come to the UK!"
None of them are true, they are exaggerations to get a specific point across. ("It'll spoil Christmas if I am ill," "I'll get told off," "Lots of people want to move to the UK.")
The facts are that an awful lot of people do indeed want to move to America to live. It is massive and diverse, in terms of geography and people. I used to think they were all gun-wielding lunatics, but then I went there and realised that I was just being ignorant. They're just normal people who happen to live in America.
What I thought:
-they all carry guns
-they are all strictly Democrat or Republican
-they've got no sense of humour
-they are convinced their country is better than anywhere else
What I found:
-no, they don't
-they hate all politicians (almost) equally. At least as much as we do in the UK!
-they do
-they're not so blind as to not be able to see where their country is lacking. Patriotism does not mean blind devotion.
There are certainly problems, where I went there was a lot of "self-segregation" between races for example.
America is like any comparatively wealthy country. People from poorer countries want to move their in the hope of a better life. People who have lived their all their life feel threatened. Their own living standards continue to fall, they are let down by politicians on all sides, and they don't see why they should have to suffer for the benefit of the many, many people who will keep trying to get into the country until they succeed (or die in the attempt).