The most surprising conclusion was about the final plot discussed, regarding scientific publications. The author says that it contains too much information and is confusing for that reason, and postulates it might be better to summarize the different fields and plot as a single variable.

The truth is, it is not a confusing visualization. There is no rule that says to remove variables for the sake of reducing a variable count. It is useful to see that health sciences stands apart from other fields, and other points can be seen as a cluster or examined more deeply by the reader. It is actually one of the best plots shown in the entire article.

In effect it is a grouped bar chart, a visualization that many publications shy away from in favor of stacked bars. While that is good for showing a total, it is often a less effective way of visualizing data—it's difficult to compare magnitude of anything but the base bar. That fault can be seen in the stacked bars of the budget surplus example, which still exists for the improved version.

At any rate, I'm glad the Economist is looking to improve their visualizations and isn't afraid to share mistakes.