It doesn't. The last real application of Sia that I heard of during the previous crypto boom basically sounded like renting your HD space out to people who would potentially use it to store illegal content.
1) If childporn was not banned, how many people would consume that content anyway?
2) What about hyper-photorealistic childporn movies with fictional characters and future rendering technologies? How will you tell the video is true or not and worth to be removed?