“gratuitous or offensive violence with a high degree of impact or detail”
Gratuitous ... does not sound correct. Indications are that this attack was not randomly targeted or without a purpose.
Offensive ... makes it more worthy of attention, not less. Should genocide also be hidden because it is so offensive?
High degree of impact ... because it contains important information about the social climate that can help people protect themselves and each other. How is that a reason to suppress?
Or detail ... that is important for judging authenticity, to be harder to fool.
Australia's rationale amounts to "we need to control your reality so that you don't get out of control". Wherever this leads, thanks for pushing back, X.