For instance, if I select 4 objects on the page, and under the transform docker, choose to rotate 90 degrees, it rotates the entire selection 90 degrees. Is there any way to have it rotate each object 90 degrees (about its own individual axis?)
Only with a macro I think, which you can't do on a Mac.
Alternately Apply to one object, select each other in turn, Ctrl-R
Macro can do that, similar task look here
https://community.coreldraw.com/talk/coreldraw_graphics_suite_x7/f/coreldraw-x7/48119/labels-rotating/230875#230875
(macros cannot be use don Mac)
Alternative - using Attributes Eydropper Tool (screen capture from X5)
Macros do exist on Mac. They're called "scripts". Look under the File menu for Scripts.
Open the objects docker, find the group, expand the group tree and select the single object you want in that group.
A macro or script should be able to do this or just as above.