Film is a very literal medium. The more closely that medium approximates reality, the more literal it becomes. This becomes a real problem when we are trying to get an audience to suspend disbelief while viewing subject matter often plucked from literature, which of course is a FAR LESS LITERAL medium.
The most fantastical storyline can seem plausible in text, but completely fall apart once transferred into a more literal medium, where we are required to experience it from the outside (ie watching it) instead of from the inside. Paradoxically, the more we fool the brain into thinking it's looking at something real, the greater this problem becomes.
High frame rates look wonderful on sporting events and on documentaries, where the ability to trick the mind into thinking it's watching something real is actually a benefit. But on a movie taking place in a fantasy world populated by wizards and dragons and Hobbits, the additional visual realism can easily interfere with our ability to appreciate what we are seeing. In other words, we begin to feel like we are watching actors performing on a set instead of characters experiencing life in an imagined world.
Perhaps it could work if the director found a technique for removing some of the realness from the presentation.