For Drive Your Plow, I didn’t know the genre. I knew I was going to read it, so I didn’t look at the book jacket. I didn’t read someone else’s thoughts first. If you’re looking at reviews to decide if a piece of media is worth your time, you’re not going to be surprised in the same way. You cannot be, simply as a function of how time and/or brains work. You already know stuff, at the minimum the stuff I have told you. Which I don’t think is bad: your free time is limited, maybe, or you already have a lot of books and you can’t read everything! But I just want to point out that I think it is weird not to care if you know whether a book is about fantasy warriors or cowboys or Victorian-era ghosts, but do care to know that Rey’s lineage comes up in The Rise of Skywalker.