No, the actual conclusion here is "for some simple problems, pie charts are more useful than bar charts or tables".
This does not show that pie charts are not lousy. It merely shows that they are not always the lousiest. Since tables aren't really much of a method of visualizing data and bar charts are almost as lousy as pie charts, this isn't saying much.
This does not show that pie charts are not lousy. It merely shows that they are not always the lousiest. Since tables aren't really much of a method of visualizing data and bar charts are almost as lousy as pie charts, this isn't saying much.