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.

Every so often I actually consider making an ObjC library around BOOPSI and ReAction objects. One day I might actually go ahead and do it.

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.