Too bad it wasn't in The Wind Rises, some other model are though [1]. The studio's name is also inspired by Caproni Ca.309 'Ghibli' [2].

[1] https://ghibli.fandom.com/wiki/Caproni [2] https://en.wikipedia.org/wiki/Caproni_Ca.309

Instantly I thought, how can they call it 'the ugliest'? it is such a bubbly and a cute plane, I would totally have it in my garage.

Agreed! It looks like a cartoon plane, quite cute. Just imagine baby Yoda sticking his head out of that thing, people would love it.

And for everyone else that didn't read any of the text...

"We couldn’t help but think that the Stipa-Caproni looks like something you’d see in a cartoon, perhaps flown by an animal character."