From that list I've read three books: "A Brief History of Time", "Thinking, Fast and Slow", and "Capital in XXI Century". First two I've read from start to end. The last I didn't read to the end, I think I've read ~50% of it. My numbers correlate with that list, the least "readable" book in the list is the book I didn't read through.

However I still doubt the methodology. It is not obvious for me that if a book was read in full, then highlights from it would be distributed uniformly all over the book.