Like DaveR I’m confused when you insist you have always used Mac.
The Mac GUI has always done this. It is one symptom of the way the “materials” window was long ago clumsily tacked onto the Mac color chooser. Although the menu item is Window->Materials, it has never been titled “Materials” on the window itself.
I have long complained that the Mac materials window has needless and arbitrary differences from the Windows one, but, like many other Mac-vs-Windows SU GUI issues, it gets no traction.
Again, I don’t think these have ever been available on the Mac. Are you sure you aren’t confusing the “materials” window with the components window? Did you keep your prior version of SU so you can go back and verify what you say you saw (aside from disk space, there is no problem having multiple versions of SU installed at the same time)? If so, please post a screenshot.