Oh, I swear it is not inverse for chip documentation (unless it's from a Chinese manufacturer, you have to do with a 2-page leaflet for a 80-pin chip in that case). But it doesn't necessarily mean it is exhaustive high quality doc.

First, we have to acknowledge that most texts (if works for law too) are very diluted now compared to a few decades. There is a lot of blah-blah that doesn't bring information. Information density decreased.

Then, there are docs that are so big (many many thousands pages), that I am sure no editor can read them fully. They pile up copy-paste from older or similar models without checking if it applies to the chip. They don't write a clean doc specifically for the chip. So as a user you can trash parts of the doc. Problem is that you don't know which ones.

Since they don't print manuals any more, they don't have to care about fitting the doc in the book, it's no-limit.

Heh - the first computer in my home was an Osbourne "portable" - a Z80 CP/M machine. It's user manual came with a wiring diagram!

(Which I used as a ~12 year old to work out how to connect a home built 4 micro switch and 2 puch button joystick to the printer port, so I could write blocky text/graphic versions of video games I wanted to play.)