I think it was made for publishing scientific research, and you could flag the options for what you wanted checked. If you were okay without the passive voice hints, you could still make whatever you were writing very direct and concise, or less wishy washy.

This is wrong. It's a good rule of thumb because passive voice can be a common indicator of weak writing, but it has plenty of good uses in strong writing. The best case to apply it is when the object of a sentence was previously a subject or other focus of prior sentences, and so is more familiar to the reader than the subject of the new sentence. For example:

"The United States had maintained neutrality until 1941. However, it was attacked at Pearl Harbor, and then chose to enter the war."

It's extremely important in a lot of policy positions to be able to use things like "a decision was made".