This was a final thought that never got posted on the whole "Iconic Bias" kick. I started thinking about the old "Comics are for kids" misperception related to it all. On the one hand, I think we can all agree that this belief has come in part from the selection of genres and social contexts that propagated during the rise of the industry. But, on the other hand I think that a deeper issue might also be at work: the idea that pictures as a whole are somehow simple or lesser than (spoken) language.
We even see the derision of the graphic form in our speech, in idioms like, "Do you need me to draw a picture for you?" The phrase tacitly assumes that pictures are simpler than words, and hence drawing a picture will communicate the idea in a less complicated way. Now, this consideration of drawing could be considered a good thing ("Isn't it great how simple and understandable these complex ideas are presented in drawings!"), but here the tone usually remains derogatory towards graphics.
This "simplistic" perspective could also be related to the Iconic Bias issue: "If pictures just look like what they mean, how complex is that? …because we understand pictures just like we understand real life."
In this view, again, pictures are not conceptual (no mental system). Perhaps that's why people are always flabbergasted to hear that certain people or cultures have trouble understanding certain drawings or sequences of images (which does happen), as if it tears against the very fabric of their knowledge of drawings. The classic orientalist thing to do was blame the people, as if they were substandard or primitive, instead of (gasp!) seeing that their own system might be learned to a large degree and not as transparent as one would like to think.