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.)