The Power of the Dog is a rather boring film where director Jane Campion does the opposite of the Hitchcock philosophy of leaving the boring bits out. By leaving much of the boring story intact, the average movie goer is in danger of missing some of the film more important plot lines (such as the how and why Benedict Cumberbatch is being murdered by Kodi Smit-McPhee). Fortunately since many will view the film in their homes, they can easily rewind and understand why Jesse Plemons is suddenly choosing a coffin for his now deceased brother.
New Zealand is a poor stand-in for the American west no matter how much Ms. Campion thinks it does. Yes the vacant spaces of New Zealand may indeed resemble parts of say Montana, but it is the trees or specifically the tree roots seen in the forest scenes that give the location away. New Zealand is a topical climate and it shows. Apparently Ms. Campion could not leave her home so the movie, including the mostly American cast, came to her. The additional expenses of making New Zealand resemble the American west may have been better spent on some additional screenwriting.