Nobody would consider a print-out of the Linux kernel's source code to be an acceptable means of distributing it.
To the contrary, bound and printed copies of the PGP source code were used to get around ITAR export controls on crypto in the '90s.
https://en.wikipedia.org/wiki/Pretty_Good_Privacy#Criminal_i...
The claim is that it's open-source, not open-rendering. There's no thing you can insert a PDF into to be able to manipulate the design in a meaningful way.
Even as a visual reference, it's not very useful. Googling the the two main chips gives no useful search results. If you did manually recreate the schematic, you would still have no way of building anything with it.
The schematic, even in image form, is the source as far as my experience goes. No, it isn't turnkey, but the schematic (in CAD file format or not) is the design. Everything after that is primarily implementation- more analogous to modern day compilers and linkers, IMO.
Even if they gave you layout files, they would likely be both a pain, and not very useful. Like getting someone else's *.o files. You probably won't be using the same tools, and you probably won't have the same boardhouse, the same parts... I didn't really come to grips with how incredibly nonstandard (or maybe just incredibly varied) parts footprints are until I made my first >100 part count SMD board. It quickly became clear why companies develop their own parts libraries, and why they cling ferociously to existing vendors, supply lines, and specific parts.
Suppose I gave you an article/paper in a proprietary file format you can't convert, with a font you don't have, painstakingly arranged for a paper size you've never heard of, in color gradients your printer can't resolve, that uses features only a couple printers can print. Would that be helpful? Me, I'd rather just get the raw .txt file and .jpg's...
This remains an excellent reference design to build upon. The world of PCB design is more labor intensive, but this would be perfectly simple to reimplement using hobby-level PCB software.