He wrote a book in the 90's that defined crypto for a lot of people. It was the first time that I know of that this info was all collected, curated and available to the "average reasonably technical developer", without reading a ton of academic papers.

In retrospect we've learned a lot since them and no one (including the author) would recommend developers read that book first or even at all. Now we've come to the understanding that folks are much better served by opinionated cryptosystem design ("no sharp edges") and texts like "cryptography engineering" that have a better focus on failure modes.

Anyway, he's not the be all, end all expert but he has been thinking about this stuff for a long time and often has perspectives that are worth thinking about. Some of them, like his views on airline security etc are now so mainstream that you wouldn't realise he was a big part of why they are now widely held.

But mainly it's that he has a lot of pretty high level gov and industry connections that I would at least entertain his conjecture here.