Earlier quoted context omitted.
The real pain is this WAS a solved problem in computers too. Almost all of the GUI OS's had a style guide. Usually 2-3 pages at most (usually smaller) and fairly easy to follow. Then everyone went bonkers and wanted to make their own. Then dump that all into one desktop and good luck... Every app is special.
I blame Microsoft for this. They release a completely new UI framework every 5 years, completely abandoning the old ones. The design is outdated and boring. The XAML based UI frameworks look terrible if you use the default settings, and force you to customize. It's great that it's easy to create custom UIs, but terrible for consistency between apps. On the Apple side, things look a lot better. They were able to keep…
MS had it in the bag too! Everyone wanted that 'sticker'. If you didnt have it almost no one would put your software on the shelf. To get that sticker you had to pass their usability tests that followed their style guide. Then they did like you said and switched it at least 2 times ever OS release.
Plus the web got in there and there were almost zero standards there. So we ended up with dozenes of framerworks that 'do it for you' and those have at least 3-5 generations of goop.