🔖 In praise of the hundred page idea
There was a set of books by an organisation called The School of Life that I read a few of. They'd kind of fit into this, although the only one I actually own, [Eva Hoffman How to Be Bored
(https://booko.com.au/w/7760978/How-to-be-BoredThe-School-of-LifebyEva-Hoffman-The-School-of-Life) was 141 pages.
Also, I tend to think fantasy and sci-fi fiction went completely the wrong way. Doorstopper tomes to satisfy the weirdest of the fans. The Elric books were 100 pages or so and they were better than almost everything else published for the next 20 years (at least)