You will either be in sympathy with it, or not. Much depends on what you bring into the theater. It is possible that those who know most about Nijinsky will be most baffled, because this is not a film about knowing, but about feeling.
You don't need to have seen a lot of art films to love The Diaries of Vaslav Nijinsky. All it takes is compassionate curiosity and perhaps some lingering memory of the world as a child experiences it.