For me the first thing that comes to mind is Tales from Earthsea. I don’t think it’s excellent or anything and has plenty of problems but people act like it killed their dog. While it has its problems that have been covered extensively, I think it has a beautiful atmosphere and art.
IMO it would have been better received if it wasn’t advertised as an Earthsea adaptation and was just its own thing.
Tales From Earthsea wasn’t even the worst Ghibli movie. That title belongs to Ocean Waves.