However, my two boys say that this album is, in contrast, probably their favorite Taniguchi. And I think you have the explanation.
I infer, indeed (but also because we had this album through a school subscription of my second son in primary), this creation is more for a younger audience. I note also the idea of Isabellects (see comments): great suggestion for a gift to a child.
And, anyway, still a good four stars. This remains, in my view, a work of quality.
Going back to my title, an interesting interview with the author, end of the book reveals that the places, landscapes and virtually every detail of the design part of the world of childhood Taniguchi, who is and inspired by the past to introduce a story where only fantasy is added to bring a particular plot, likely to bring interest to the reader and thus contribute to the dream.