I found "The Boy and the Heron" to be somewhat disappointing. Here are some of my thoughts about it.
Pros: Visually this movie is an amazing, truly magnificent animation that has become the signature mark of Studio Ghibli. All the music and voice acting are also excellent, and fitting.
Cons: I found the movie's second half to be a mess. The first half was suspenseful and did well to establish a mysterious and foreboding atmosphere and introduce the main themes. However, the second half becomes chaotic in a way that also felt disjointed, I don't know how to explain it. Its like the movie throws a dozen random puzzle pieces at you but never bothers to connect them. One would have a better time not trying to think too much about what was going on and just take it for what it is. I found myself looking at my phone and wishing the movie would end already, all the while thinking "This is just animated "Pans Labyrinth"
Conclussion: I guess I just don't "get" the movie, or it wasn't made for me, I just think it wasn't very entertaining. At least in other Ghibli movies like "The wind rises" I was engaged through the entire movie and even found myself cheering at times. There is very little emotion to be had with "The Boy and the Heron" other than awe at the pretty animations and confusing at what is going on.