Note that comment is toward "then going into rhapsodies about how free-spirited and unencumbered and holy and mad and visionary it all is". It is entirely valid comment. It is entirely 100% valid to make such comment even if you actually like the book.
What is bad is insisting that no one can point it out. That we all must pretend that acting like that is being cool free-spirit and visionary. That we cant analyze a book and make conclusions about what it celebrates, what it criticizes and what it just describes without any value judgement attached.
Somewhere along the lines people developed extremely thin skin toward what you can say about famous pieces of art. You cant really analyze them nor their characters. You must show only unfailing admiration of the characters and the book itself.
You definitely should have the right- and there should also be a firewall to socializing such experiments damage and fallouts. I just had also very negative experiences, where the mere thought experiment was considered "heresy" and as an attempt to recruit people for such a lifestyle. I can defend the freedom while defending the freedom, while not pushing the freedom from consequences.
Just jumping back to Scott for a moment though, one suspects he probably does enjoy books about people who have broken commandments. "A terrible book" about "terrible people" suggests both that the people are terrible and that the book itself is poorly written. There are two concepts there to grasp. He's leaving the option open of a wonderful book about "terrible people".
That was always one of the appeals of the Seinfeld show for example. Well written show about some really horrible people. Fun for the whole family.