From the wording of the article, it's pretty clear that the researchers that the authors are aware of the degree of circumspection that such findings typically raise -- and that this isn't just a matter of a single associational study; but rather, a retrospective finding over many studies. Which the researchers feel should forces to consider the fact that we may be close to a tipping point, with regard to the proposed etiology at hand.

Hence statements like "We can't keep ignoring the evidence", "landmark editorial", etc.