As a developer of apps, you provide software that tries to fulfill a specific need of some subset of users (in other words, it's not merely an uber-fart-generator). You genuinely build this app to the best of your ability and push it to the app store. Users trickle in, based on the app description and find that, for example, it lacks polish or it doesn't have feature X yet, which is relevant to the app's domain and to the user, but is not currently implemented. In other words, there is a mismatch between user expectations and the app-provided experience.
Instinctively, these users feel the urge to leave a negative rating. It's a knee-jerk reaction. As a developer, I want the user to engage me, because obviously I have an app that is not quite there yet. I want the user to tell me what they want fixed before leaving a negative review, so that i can satisfy their needs without burying the app. By funneling him into such a feedback loop, I can better my app and in turn help him fulfill his needs best.
Is this unethical, or evil? I say no. Apple outright banning these unethical -- as the author considers them -- design patterns, would also have a detrimental effect on many legitimate use cases.