Color phtography was hardly easily available from the early 1900s. It would be theoretically possible for them to have shot in color, but it would have been exp

Color phtography was hardly easily available from the early 1900s. It would be theoretically possible for them to have shot in color, but it would have been expensive, inconvenient, and much harder to reproduce; most images were shot in black and white well through the 60s, and people were used to the format. It's like asking why they didn't preserve all their galleries in 3D VR starting from the 2000s; it would have been possible, but not worth it.