Bob Dylan (Robert Zimmerman), was a great lyricist. In fact, in my opinion, he was far better at writing songs than he was singing them. To many, it was his slurry, nasally voice that helped make him unique and loved.
I think we just had a great bunch of talented artists during the 70s although many did not live to enjoy a long life. Hendrix, Joplin, Croce, Morrison, etc., passed on in the 70s.