The Wizard of Oz is iconic American cinema at its most whimsical. A film as magical, colorful, and lively as this one is enough to satisfy the average viewer of any age, but as Salman Rushdie points out, there are a lot of other thematic elements at work that make the movie more complex and thought provoking. He makes a point of stating that the film highlights the inadequacy of adults, an idea I had never thought of, but upon a critical reflection of the film, seems to hold true. Auntie Em and Uncle Henry are both down-to-earth, practical, and emotionally distant, while Dorothy has her head up in the rainbows and is seeking emotional stimulation. The Wicked Witch/Ms. Gulch is an adult and the primary antagonist, the Wizard of Oz is a grown man, yet turns out to be a egomaniacal liar with a projector. Whether or not the Cowardly Lion, the Tin Man, and the Scarecrow count as "adults" is up to speculation, but I would place them in the "trusty steed" category. They aren't old or young, they simply are.
It is also interesting to consider the cultural context in which The Wizard of Oz was released into, and how its fantasy themes were groundbreaking in America, these sort of adventures were common other places (India). I also like how Rushdie mentions the lack of a religion in Oz, and how this inclusion helps to focus the audience's attention on Oz's characters instead of Oz's culture. The Ozlandian paganism lends the film a lighter tone and helps create the fantasy world millions have come to know and love.