This is one of the good ones. However it reflects as much the passion and skill of Hayao Miyazaki as his old age confusion. His latest "last movie" starts one way and ends (abruptly) another. It has elements from his own life, his previous work and some new ideas, but the gist of the film is reconciling with loss and moving forward, recognizing there isn't much one can do. A very old man mentality in a movie about a child entering a magical world filled with wonder and dream logic.
The animation was so beautiful, the story a bit disjointed, but quite captivating. It was the ending that kind of disappointed. This film has been a long time in the making (in 2019 it was 15% complete, allegedly, with Miyazaki directing a minute of the film a month) and it shows.
The Japanese title is "How do you live?", the same as the Genzaburo Yoshino's instructional coming-of-age novel that Miyazaki's mother gifted him. In the film, the boy finds the book with a message from his dead mother, instructing him to read it, but it never goes anywhere. There are a lot of other hints and symbols that are quite opaque to non-Japanese, so I felt that I've missed chunks of what the movie was supposed to convey.
Perhaps the most interesting quality of the film is how easily it can be interpreted multiple ways, the ambiguity both confusing and thought provoking. As we experience dream and child logic we get a glimpse of the transmuted reality underneath. The grief, the loss, the benevolent yet oppressive culture, the futility and pain of war, the missing and missed parenting and so on.
Bottom line: is it a masterpiece or a slice of Miyazaki, jumbled beyond recognition? Both. I felt it might be a fitting farewell film, but also that I missed so many meanings from it. I liked it.