I like Zeppelin, but they are a glorified cover band. Pretty much every song on their first four albums is a cover, and most of them unattributed.
Yeah, but come on.
They’re a cover band about to the extent that Apocalypse Now is a cover of Heart of Darkness.
What a strange thing to say. Whoever they were covering must have been pretty obscure because I had never heard the songs until Zeppelin recorded them. And the group had a unique sound that made them easily distinguishable from other groups which were popular at the time.
If you're looking for over-rated groups, I think you need to look elsewhere.