As Tabwriter notes, Nathan only outlaws "casually [word censored]" reviews from writers; he outright states that he thinks "thoughtful" reviews are just fine. So do I. I love reading reviews and learn a ton from them, both about the subject matter of the book, and about what appeals to readers, or turns them off. (I have subscribed to The New York Times Book Review for years, along with, off and on, other review journals such as Horn Book, BookList, and VOYA, for which I used to review). I think we're all smart enough to decide when a negative review is fair and when it's written with an agenda or for the reviewer to show off. Nor do negative reviews necessarily keep me from reading the book. For example, Julia Glass's second novel got a lukewarm review in the NYTBR, but I'd loved THREE JUNES so much that I was willing to follow Glass anywhere. I bought the book, understood the reviewer's point of view, but loved the book anyway, for reasons the reviewer didn't mention.
Thoughtful reviews help me see things in books that I might not have noticed on my own. They alert me to books I want to read, they make me think about my own writing. I particularly like reading reviews by writers because I like to see their perspectives on books, to see what it is they notice.
That said, I do have some shame about reviews I wrote years ago for VOYA where I might have put a sense of my own cleverness above the writer's hard work. I was submitting and being rejected at the time, and I fear my reactions to some books might have been based more on my impression that MY book that got rejected was way better than this book that got published. Which leads me to my point: I think I used to fit into one of the most dangerous categories of reviewers---writers who are working very hard to get published but who haven't yet had a book accepted, and whose envy and frustration sometimes comes through in their reactions to the books they are reviewing.