The author Marie-Joseph Peyre lived in the 18th century and was himself an architect. That I an explanation for the title Oeuvres d’architecture, which means as much as “the work of art in architecture”.
If we take into account the time in which Peyer lived, this makes perfect sense, since he was in the midst of the Enlightenment, in which part is also a revival of antiquity and thus explains the admiration of ancient architecture.
He structured his book in such a way that he always described the buildings mentioned in it with a drawing and a small text. Therefore, I assume that the book was not necessarily for architects, but more for people who had the power to build the buildings he depicted.
More precisely, and from the text, Marie-Joseph Peyre addressed his book to the then French King Louis XV. Presumably, he hoped that his support and help would bring ancient architecture back to life.
It is also interesting that the whole thing then actually moved in this direction with neoclassicism in design and architecture. However, it is also clear from her texts that she hoped that with the construction of these beautiful ancient buildings, the world would become a better place. That thereby, so to speak, the problems disappear, but I believe less.
Translated with www.DeepL.com/Translator (free version)