I happened recently with my girlfriend and I after watching The boy and the Heron, the last Miyazaki.
I was disoriented, trying to make heads or tails of what I just saw, and she was completely happy of all the poetry and symbolism she just saw.
Some art pieces are not meant to be overanalyzed. They are meant to be felt.
I had the same experience with the movie. Even though I knew up front about Isao Takahata’s passing, I struggled to make all the imagery fit into my expectations of a “coherent” story. At one point I just had to let go of my search of any overarching analogy, and just enjoyed the fireworks.