I rented this so I could say that I fairly judged it. The idea buried somewhere deep inside has potential but it's suffocated in egotism and a sort of displaced want of wellbeing. I am not autistic and I can't speak for the autistic community but the portrayal of autism here is extremely limited at best and completely dehumanizing at worst. More than anything, at least to me, it felt like a vanity project for Sia. After watching this I have to question if her heart really was in the right place or if this is just a terribly misguided attempt at something far beyond her capabilities as an artist. The music and dance numbers don't seem at all conducive to an audience that sometimes suffers auditory and sensory disturbances related to loud, clashing sounds and vibrant strobes of color. Ontop of that, the vision doesn't make much sense but rather paints autism as a type of magical thought process where the subject exhibits a life of hypervigilant lucidity and sudden throes of theatric fun and colorful disassociation in their mind. There is nothing charming or educational or enlightening about this movie, sorry to say, and the criticism is well deserved.
Moving on from those critical flaws, the writing is abysmal and the storyline is as linear as a storyline can get. From the very beginning with the death of the grandmother each character is introduced as a trope to keep the plot moving as opposed to building upon it. If nothing else Music should have been the focus of the story not the side supporting character to Zu, and she should have been dialed down so she didn't encapsulate one small fraction of the autistic spectrum. Unfortunately her presence felt a lot like a plot device. Selfish is the only word I have for that kind of medium. The music and dance numbers are very good and very entertaining but they do not work in a film like this, which is why I think Sia did not make a movie about an autistic character but made a movie showcasing her artistic style instead with a very superficial portrayal of autism plastered over top. Intentional or not, it's badly done. The most positive thing I can say is that I enjoyed the songs but good songs do not a good movie make. It's a terrible shame because the potential is there and could have been something groundbreaking had it been handled by an experienced director and screen writer instead of someone with no background. Sia had a place in this kind of film just not at the helm.