Do 3D bar charts have advantages over 2D bar charts?
A relevant source seems to be


  A Psychophysical analysis of chart readability, 2001


Sadly, I don't have access to it.

Anecdotes

If you have an area chart, giving it a 3D-effect and rotating slightly can help readability. But I don't remember a context where you could not have used a line chart in the first place.

Bad sources


PRO: Looks good (targetdashboard.com)
CON: Values are harder to read from the axes only - you need to add values to
the bars themselves (targetdashboard.com)