I have stayed out of this thread but now I must enter the fray.

Baum was not writing a story about populists, progressives or
prohibitionists but rather it was a prophecy. He was writing of our times.
Here are my thoughts:

Dorothy represents the poor little end user lost in the magical world of
computers.
Toto is an allegory for her system, as in, "It runs like a dog."
The Witch of the East is actually from Armonk.
The Witch of the West represents all of the scary people from Redmond to
Sunnyvale.
Scarecrow represents the system administrator that feels that Database, i.e.
brain power, is  not essential system operations.
Tin Man represents those solution providers whose solutions never get to the
heart of the problem.
Cowardly Lion represents CSY, too afraid to stand up in the market place.
The Wizard represents M$, all bluster and no substance.

Joseph "an OZ of prevention beats a LB of cure" Rosenblatt

PS If anyone takes this seriously shame on you. : - )