The worlds population living on $10/day, will have no use for a book on a niche aspect of type systems. The majority of people on that wage will probably not even access to a computer.
Most people, at any income level, would not find value in this book. The fraction of people who find value in the book maybe correlated with income.
There are a large number of people who might benefit from access to this book (or similar books) would can not afford to legitimately purchase it.
Given that only a small fraction of the world population can afford this book (I estimated 5%, happy entertain other estimates) it seems likely that the majority of people that could benefit from access to this book, could not afford to buy it.
Most people, at any income level, would not find value in this book. The fraction of people who find value in the book maybe correlated with income.
There are a large number of people who might benefit from access to this book (or similar books) would can not afford to legitimately purchase it.
Given that only a small fraction of the world population can afford this book (I estimated 5%, happy entertain other estimates) it seems likely that the majority of people that could benefit from access to this book, could not afford to buy it.
I find that unfortunate.