I've never once encountered such a book. The only times I see cursive are stuff from older relatives, and they all write differently to each other so it's just a matter of familiarity, and on headings or labels trying to look fancy.

Sometimes it comes up in old stuff for academic or personal interests but "knowing cursive" is often secondary to understanding those. Letters or papers intended for others are often perfectly legible, personal notes are a total mixed bag. (Looking at you, Charles Darwin.)

Because it's a waste of time, and a lot of people were taught in a way that wasn't the easy, quick way you seem to think it was.

The way they taught me was to write the alphabet in a new script over and over for about an hour a day twice a week for several years. If you had poor handwriting you had to do it more, and you could fail lessons based purely on "didn't shape your cursive S correctly".

Then you leave elementary school and teachers immediately switch to saying they won't accept assignments in cursive, and then in highschool and college they won't even accept handwritten.

Slide rules are also easy to learn, but we don't teach them because there's no point to it.