An interest in "outmoded technology"=an interest in the history of science. Anybody who lacks that interest seems to me to be very short on intellectual curiosity.
Quite apart from that, this is an extremely well made film, at times reminiscent in the early factory-scenes of the great "city symphonies" of the late twenties. Montagu did not make many films but, to see what he was capable of,look at the wonderful "Blue Bottles" (one of a series of films of H. G. Wells stories starring Else Lanchester which he made in 1928. It is worth a look. It is one of the best comedy shots of the decade.
As for the "class/imperialist" aspect, this is undoubtedly there, but do not overlook the possibility that Montagu (a committed communist who was involved in documentaries on the Spanish Civil War at this same period) was having a bit of fun in this regard (particularly the absurd but craftily edited bedside interview with Lady Houston). You need to know a little about the people involved before you assume that such things are naive (compared to us, who are of course all-knowing) or that a certain irony is not intended (emphasised at points by the music). For anyone English, it is quite evident that the "stiff upper lip" is intended humorously (monocle and all). It is the characteristic image that the British liked to give of themselves at this time - of eccentric (but courageous) gentlemen/amateurs.
It is of course in many ways a false even hypocritical image for an imperialist power with a vast empire but it was very valuable in propaganda terms both before and during the war because it enabled the British to distinguish themselves very sharply from the professional technocratic Germans. And no one fell harder for this sort of stuff than the US who relayed exactly this image of Britain in all their own wartime propaganda.
