The custom-fitted wooden tool box speaks of a time when the home or even pro mechanic didn't so much have to be "subscribed" to the yearly additions from a variety of parts/tool vendors, when the pace of development was much slower.
When crafting a wooden box for the specific tools-of-the-day would have been more practical.
Today, even the shape of the same tool often changes for no apparent reason, other than usually to add distinguishing 3-D plastic handles or a new safety feature.

Most distributor catalogs were a whole lot thinner back then, barely needed to be revised annually, and shops didn't need to stock several different chain-connector links/pins or dozens of different cartridge bearings..