The funny part is that he didn't even care to generate a different number of reviews for each book, or to add a few 4's in just to make it more realistic. He used the exact same number of reviews for many books, and all are full 5's!
That would be the result if it was automated, such as either a script or the AI itself instructed to write books on various subjects, selling them on Amazon, and then reviewing them. I don't see what can be done to stop this trend since it's 100% certain it will become ubiquitous.