No, an incredible feat of mathematics!
Tom Ritchford

From Britannica: “The words engine and ingenious are derived from the same Latin root, ingenerare, which means to create. […] The scientist adds to the store of verified, systematized knowledge of the physical world; the engineer brings this knowledge to bear on practical problems.”

Based on this meaning of the word, I would argue that Riemann’s paper is indeed a marvelous example of engineering.