Random yes, useful also yes: AmigaOS has a C-based object-oriented interface to its Intuition UI library called BOOPSI, and having ObjC available makes it much nicer to work with BOOPSI objects.
Apparently, MorphOS already has out of box ObjC developer support for MUI, via ObjFW. But that requires using MorphOS and MUI, which not everyone necessarily wants to do that.