I watched Boy and the Heron for a second time. I did not enjoy the first watch.
It is good, but it is very Miyazaki "meta". I'm convinced that to enjoy it, you have to understand his visual language, his philosophic contradictions, his past, and his fraught relationship with Ghibli and letting it be its own thing, out from under his shadow.
I don't really know if that makes it a good movie, but it makes it one of my favorite Miyazaki movies.