Yeah, I mean a gargoyle is about as purely ornamental as it gets. It’s essentially a decorative sculpture — art for art’s sake. Cornices, friezes, cupolas and (non-radio mast) spires are all prime examples as well.
I’d also call that circled bit of masonry (?) above the window ornamental. I guess you could argue there’s a sense that it’s supporting the floor above it, but it’s not making some kind of optical illusion of structural support.
These flat pilasters are a better example of the kind of thing that drives me crazy:
Like, what’s the point of this?