I don't think he was saying what he believes.
I got the impression that he was playing devil's advocate; essentially saying what he believes that others believe, and how they justify their stance.
Looks like he went to Wales as a child, so in the absence of any other information, poached from Wales perhaps
No, thats not right. I would say that MOST white New Zealanders are third generation or more. A generation is about 20 years.
I was born in England but my daughter was born here, and so was her daughter, so that makes her a second generation kiwi. She has just turned 14, so within the next 10 years, she may have children of her own, and they would be third generation, from a mid-1960's immigrant; me!
Immigration to NZ goes back well over 150 years.