An inherently immoral philosophy because it encourages a failure to act. An it harm no one... means do not actively harm anyone. Fine. Doing harm is, in fact, bad. However, failing to prevent harm is also bad. If you live by [The Rede] you can fail to prevent harm if the [prevention] of harm is not what ye will. Also, if actively doing good deeds is not what ye will, then you do not have to do them.

Although living by The Rede does not necessarily make you [a bad person], it also does not make you a good person.