TLDR: the main file has the most commits and is probably also the biggest file in the project, so it has the most pain points. News at 11.
If it’s supposed to be an ad for the 2 mentioned books, it’s a bad one.
I’ve seen this approach as https://github.com/garybernhardt/dotfiles/blob/master/bin/git-churn. But going further and assuming these files are the “pain points” seems like a stretch. In fact, I think a strong power law is usually what you want here. The alternative, a flat distribution, makes it harder to find your way into a codebase, because every file is equally important.