So let's say an app erases your hard drive if you use it the wrong way, but it is easy to fix with a registry tweak anyone can do. Should we really only drop a personal note to the author instead of warning everyone it sux0rs and having a discussion in public where people can become aware of the problem and work around?

Pointing out problems with things is one of the most useful parts of communicating with others, and this article advocates not allowing it most of the time. Would you read a publication's movie or restaurant reviews if the reviews only ever said good things about the movies? I sure as hell wouldn't, I'd look for one that gave the whole picture.