NOTE: This article contains personal opinions.
I recently read about a new book that documents all the readable tombstones in a cemetery and provides a map of that cemetery. The single copy of this hand-made book is available at a public library near the cemetery that was documented. That effort results in a valuable resource for anyone researching ancestry in the area IF THEY CAN TRAVEL TO VIEW THE BOOK. For some descendants, that may require travel of thousands of miles.
Of course, thinking about the publication of a single book immediately begs the question, "What about those of us who are unable to travel to a specific library that might be thousands of miles away?" I will suggest it is time to change everyone's thinking about publishing.
The "old mentality" always has been to publish a book in order to preserve information and to make that information available to everyone. Of course, this also implies that the information really is available only to everyone who is able to travel to the location of the book or is able to purchase a copy of the book.
In reality, that's not a very good solution.