I'm surprised you don't think there could be any more to art history/criticism than either "Look, it's a picture of a duck" or postmodern babble. There is less postmodern babble in nearly all fields in the humanistic disciplines than most people around here seem to think.
My knowledge of art history specifically is limited to a single college course, but I've been exposed to literary criticism in a little more depth. At least in that field, the predominant failure mode seems not to be postmodern babble (there's some of that in a lot of contemporary work, but it seems more in the nature of a stylistic tic than an actual fixture of thought) but what I might call promiscuous application: that is, readings of a work are decoupled from the needs of readers and writers generally and selected according to what looks fresh and interesting to the literary criticism community. This produces a lot of entertainingly hyperspecialized but ultimately sterile interpretations, a lot of ingroup pandering, and a lot of political grandstanding, but not -- as a fraction of the whole -- much insight into the actual mechanics of literature.
That's not to say that I've gotten nothing out of it; I have. But it tends to take a lot of digging.
There is a strange and not obviously sensible blending of cultural theory and literary criticism in academia. So often you end up reading an analysis of a work that exists to illustrate someone's theory of culture rather than an analysis of a work that exists to illustrate important aspects of that work. Freud gets invoked far too often, too.
In school we learn wonderful things like how to find integrals, solve equations, and how to calculate valence electrons of elements based on their atomic numbers. Because, obviously, they will be very important in our futures -- especially if we become artists, musicians, writers, actors, and business people.
We learn so much in school. Yet, when most people look at paintings they don’t truly understand them. When most people listen to music, they don’t really know what they’re hearing. Most people would fail simple music theory tests, even though many have listened to music most days of the week since they were babies!
Similarly, if you have working eyes, you should ask “Why do shadows look like they do? What color is snow, really? Can I predict the colors of different colored materials at different times of the day? If not, why? I have been seeing them for years, haven’t I?”
I think the problem here is that people can’t understand what is really important. Calculus, mechanical physics, chemistry, microiology, etc. are interesting to learn, perhaps. But, they are relatively advanced topics. People don’t use them in daily life unless they are professionals. Why not learn things that we think about every day instead of those that will frankly be useless to most?
Why don’t we learn how to understand our senses?
Learning about sight, sounds, thoughts, etc. should fit in somewhere in the first year of high school. Everyone needs to learn the physics of art and color (e.g. this and this), music theory, rationality, and logic.
For example, why should people start learning (or pretending to learn) philosophy, the art of thinking, in college? Should we be able to make life-changing decisions without even knowing how to spot errors in our thinking?
As a science researcher, I know first hand how hard it is to find a good balance between being well versed in worldly topics and being focused on a field in order to excel in it. But, both of these areas of study should not be called the true basics, in my opinion.
As president of my school's philosophy club, I took a different approach to teaching the basics of philosophy and thinking than traditional classes do. Instead of asking students to discuss the lives and ideas of famous Greek philosophers, I asked them to analyze their own lives and make their own philosophies. As expected, they were terrible at it at first. But, by the end of the year people began to actually think about the world around them.
So, my point is that we should -- in life and in school -- emphasize actual everyday thinking more.
The biggest challenge is that it takes so long!