I can relate to that space. In the early 2000s I was a finish carpenter in Wyoming and, as you know, storage space is often lacking in many house designs. Architects also reuse designs over and over - there may be 50 identical houses sprinkled across the state, despite how “custom” the plans were originally. Architects have a way of guiding choice that miraculously match up with a design that’s already in CAD, with a few changes. Wyoming is also the wild Wild West with many rural areas not having as many building codes to follow outside of city limits, at least back then. That influences the number and type of changes made on the fly. It wouldn’t surprise me if the architect was in Riverton or Casper - those working around Jackson are often overpriced.
If the house was originally designed for premade trusses, we’d often suggest a stick built roof so storage space can be built into unused spaces, and it gives more work to the carpenters - win win. That kind of change isn’t usually done when the space is inspected since it would require an engineer to approve the change from trusses. I’d expect the original design to use trusses over the bedrooms and garage and not have that storage space at all. The bench for the mountain lion on the other end of the room was probably was in the design - some like it, and some don’t then we’d frame it in.
Great house and great location!