While that’s reassuring in a way, it goes deeper than that.
The point is really about how much duplication can exist in a piece before being considered plagiarism. This has impacts far beyond Led Zeppelin and any potential monetary loss for them.
While I do not defend outright plagiarism at all, it is still true that there are recognized musical conventions, such as a chromatic, descending bass line, that are common to all forms of music. In addition, it is a simple fact that there are only twelve notes in a scale. Some overlap is inevitable.
The outcome of this lawsuit may have the potential to impact other artists, as well.