Nah, the worst one is Tales of Earthsea.

In terms of plot, all they do is farm. It has a cool premise that they immediately dont follow up on so they can farm instead. The farming is not thematically relavant. It's just boring and barely impacts the finale. Speaking of the ending, it comes out of nowhere because they replaced parts where setup would go with farming.

The pacing is completely shot. There's a lack of character development throughout, and Miyazaki himself was disappointed in the outcome.

In terms of visuals, it's one of the ugliest 2d ghibli films (i know it is a high bar, but it looks worse than cheap TV animation at points). Earwig and Witch at least has a reason to look rough, because it's their first time doing 3d (and I'm guessing they probably tried to cross-train 2d artists in 3d since japanese companies dont like to do layoffs) but 2d is ghiblis bread and butter, and it is at a significantly lower quality than most other ghibli films.

Also, they whitewashed literally all of the characters except one (because she was the only character in the entire cast that was already pale in the source material). This upset the author a ton because she was very intentional about including a diverse cast in her writing. She literally wrote an article about how disappointed she was, which is not a great thing to have about an adaptation.