My parents bought a relatively inexpensive television in 1987 and it came with complete schematics, printed out as an addendum to the user manual. I was more excited about those than the TV itself because I had just learned to read schematics from one of the Forrest Mims books at Radio Shack a few months earlier. This was in the US and I am pretty sure it was made by Emerson.

A dumb brand name dryer we got from Home Depot a few years back still has one of these. It was a breath of fresh air to unfold it and pretty quickly determine what part was bad with a multimeter and some high school electronics education.

Some test instruments still come with "theory of operation" documentation. Those are tons of fun to read.