Daoist_dan There's something to be said for letting authors remove reviews, though.
Some people leave 1-star reviews with zero chapters read, while freely admitting that they haven't given the story a try. That sort of thing is not only unhelpful to readers but can also tank a new novel's rating before it gets a chance to gain traction.
Critical reviews are a different matter, of course. If a reader doesn't like a novel and leaves an honest review explaining why, it provides value to other readers.