alt Hacker NewsFrom the article: "clerical errors, natural disasters, and pension fraud were better explanations for the proportion of centenarians “discovered” in these discrete regions of the world."
That was discovered in Japan around 2010.[1] The Tokyo municipality sent out people to visit everyone over 100 to find out what they were doing right. What they found was that about 80% of them were unaccounted for, but collecting benefits.[1][2]
[1] https://www.bbc.com/news/world-asia-pacific-11258071
[2] https://www.npr.org/2010/09/20/129992827/tracking-down-japan...
To be clear, your quote is not a claim the article makes. That sentence in the article is paraphrasing Saul Newman's claims. The article itself explicitly disavows the claim, treating Poulain and Buettner generously and giving them paragraphs upon paragraphs to respond (Newman got two paragraphs; Poulain and Buettner get twenty). The article's actual position, like the headline, is that "twenty-five years after the first blue zones were identified, it’s impossible to say whether they were ever real or not."
(I happen to agree with Newman and probably you -- it seems like there is a very clear answer to whether blue zones were ever real or not.)