I agree - it is a typical product of its time, like the work of Detaile, Lienhardt and Humbert, it is a re-hash of different - mostly unsourced series of plates.
Richard Knötel was really the first - and in my view - well advanced for the "Zeitgeist" - to consult memoires and contemporary picture manuscripts to find out what really was worn and not what the regulations say.
So we get treated as you say with beautifull objects of miliatry art - but of limited value