That really depends on how you define "blockchain researcher" and, in particular, how close the research must be to hard science (as opposed to engineering implementation) to satisfy your definition. The researchers I personally know working on blockchain technology are all scientists in either cryptography or distributed systems. The author's background is economics, which provides a plausible reason for interest in blockchain technology, but not nearly enough of an academic grounding in the subject on its own for research purposes. I also don't see any actual publications or experience on his public CV that indicates particular expertise in the subject.

That said, he certainly could have an out of date CV and brought himself up to speed in the subject on his own, which wouldn't surprise me since he's a PhD student. More to the point, what he wrote in the article should probably be considered on its own weight since its content isn't so specialized and complex that we have to defer to academic expertise for confirmation. He probably shouldn't have made such an easy target of his title, but the salient points of his post can be reviewed independent of the title's merit.

There's an "About" page on his blog.