SmartArt created in PowerPoint 2016 for Mac isn't compatible with versions of PowerPoint for Mac that came out prior to PowerPoint for Mac 2011. If you try to save a presentation that contains SmartArt as a .ppt file (which is compatible with PowerPoint 97-2003), the SmartArt graphic is converted to a picture. If you apply formatting to the picture while editing the presentation in PowerPoint 2004 or earlier, then the picture won't be able to revert back to an editable shape in versions later than PowerPoint 2008.