I think the biggest core problem with Houseki no Kuni that drags the rest of the series down is that Phos doesn’t achieve enlightenment. He has it forced onto him. And that is so incredibly not the same thing.

Phos doesn’t learn anything. He doesn’t grow or change organically. Every single change he undergoes is one forced upon him by the narrative. By the time of the hiatus, he’s been reduced so much that there’s literally nothing left of him. He doesn’t even recognize his old self or even know why he did anything in the first place. If this is meant to be symbolic of him giving up the material plain a la enlightenment, it fails because he never actually gave it up. He was violently kicked out of it by Aechmea. 

When you get right down to it, Phos has no agency. He never accomplishes anything by his own will. Everything he accomplished was due to someone else’s manipulation. It goes beyond him failing everything. He’s just a pawn in somebody else’s game. Not only is that not exactly a compelling trait in a protagonist, it also goes against what enlightenment is supposed to be, doesn’t it? Based on the literature I’ve read, walking the Eightfold Path is supposed to be incredibly difficult. You have to devote yourself to it wholly. But instead of choosing to walk it, Phos was hustled along at gunpoint.

And even then, I’m not sure he actually did hold true to the Eightfold Path. Because the Eightfold Path is one of broadening compassion, but Phos only becomes more self-absorbed as the story unfolds, forgetting his promise to Cinnabar, shattering gems left and right, asking Sensei to pray “for me” when the prayer would affect everyone, etc.

The Buddha achieved enlightenment when he mediated under the Boddhi Tree for 48 days. Nobody forced him to do that. Nobody chained him to the tree or threatened his family if he didn’t. That’s something he chose to do. It was act of will. But this series sees Phos’s choices as irrelevant. Phos didn’t sacrifice himself for everyone else’s benefit, somebody else chose to sacrifice him. Neither Phos nor Aechmea are true Bodhisattvas because one was tricked, and the other did the tricking.

Maybe that’s the point. Maybe this whole story is meant to be a deconstruction of the journey toward enlightenment. But you can’t deconstruct something without holding true to what it is, and this manga (unless there’s something I’m missing) doesn’t even seem to understand enlightenment well enough to deconstruct it.

At any rate, “The Eightfold Path actually sucks lol” doesn’t seem worth it as a core theme.