Considering how fashion-driven the programming world is, popularity (of the lack of it) of a language or technology says very little about how powerful it is. Prolog's way is very powerful, it's just very different from just about every other language out there, which makes it hard to learn and harder to master.

(As an aside, in my experience, people who believe that "programming == math" seems to be mostly attracted to languages like Haskell and OCaml, not so much to Prolog.)