You can make a fast action rod out of anything. Action refers to where the rod bends not how stiff it is.

A straight taper graphite tube would have a very slow action. A highly tapered glass tube would have a very fast action.

Fast action rods just weren't in vogue until later in the 20th century when graphite just happened to be taking over. But I do have an older Shakespeare President fly rod, all glass and it is the fastest action fly rod I have ever owned.