I think the study conclusions overlook the fact, when evaluating the sorting systems the test subjects devised, that the messy cubicles weren't created by the test subjects. They were placed into someone else's mess. However, the study does acknowledge the effect that being placed into someone else's mess likely is responsible for the test subjects' desire for simplification. So your messy cubicle may, or may not, say anything about your organizational skills, but it is likely to cause your neighbors to clean up their cubicles.
I don't believe either a clean desk or a messy desk is right. What matters is whether your degree of messiness makes you more effective, as discussed in the article What's Wrong With A Messy Desk?

