Looking at that image from a century ago, the most striking difference from today is how much more manicured the vegetation is compared to today.
In particular the ancient-looking Hawthorns which punctate every wall and field margin have clearly grown up since the end of the Great War.
I suspect that the photo at the top of the post marks a time when intensive grazing and management of the valley was tapering off. The wars of the 20th century will have taken away many of the men who worked on the land. Specifically, the generation of character Hawthorn which are such a feature probably got going during WWII.
The same may be true for WWI and many of the trees in the higher parts of Spring Wood…which look to be about 100 years old.