Sally Jane Black’s review published on Letterboxd:
The prevailing emotion in this film is anger. Rage, hatred, loathing. It is such a bitter, angry film that even the clouds in it seem to seethe with it. What we see is the tale of a proud, powerful man whose rule is so absolute he cannot fathom the fall he is about to experience, and what we see is the fall of a man whose past has done nothing but maim, murder, and malign those around him. He has forged his fate a thousand times over in warfare and conquest. When he demands his sons split evenly the kingdom he has created, he naively believes his authority will persist beyond his willingly ceding that authority.
This is not King Lear. King Lear, for all its better qualities, is merely a play. Stages can be amazing and impressively wrought, and they can convey much to the imagination. But this is a film, and on film, we have the luxury of an even broader canvas. With a film comes not just great vistas and epic warfare, but also more deeply wrought characters and narratives. Gone are King Lear's daughters in favor of Hidetoro's sons. I was at first worried about this change, but as the film progressed, it clicked: Kurosawa's story is a story of how violence begets and teaches violence, and to tell that tale in the setting he had chosen, sons were a historically more likely to drive the story.
And that is the core of it here. The violence begetting violence, that is. Hidetoro's life as a warlord taught his sons no method for living peacefully, and his banishing of the one son that somehow might have managed this ensures this story will play out in blood and smoke. At every turn, when there seems a chance for peace, for a cessation of the darkness, his past as a warlod comes back to haunt him. Lady Kaeda is the most obvious part of that, but everywhere peace is defeated, more than anything, it is the sins of Hidetoro's past returning. It is etched on the souls of two of his sons.
And so when the Fool curses the gods and Buddha and any other force that will listen, it is not, to my ears, some atheistic rant, not some nihilistic condemnation, of the Divine's hand (or lack thereof) in the bloodshed--though I would not be surprised if that was some of the intent--but of the inevitability of the dark fate the story depicts, a fate determined by a life's worth of bloody decisions and cruel triumphs. This is the anguish of one who knows--and the Fool makes it clear how much he knows the whole way through--the price paid for loving the fallible (and therefore, capable of evil) human race.