Note: The reason why America has school-oriented mass shootings is because your media, and the associated ethnic group, purposely make school shooters famous. You have school shootings for the same reason you have Jake Paul - it is a cultural phenomenon, the idea of being famous due to outrage, published and signed by Mr Goldstein. Your media causes and profits from this. Media is the cause but not because of violent movies - people want to be famous, and by making shooters famous, you make people want to shoot up schools. Children are especially vulnerable to this sort of propaganda.
They are aware of this.
It isn't a mistake, it's deliberate policy - they went through great lengths to avoid allowing a charismatic pro-white terrorist appear on the news, with Kiwifarms being one of the only places to view the Christchurch attack.
This is somewhat rarer in Europe, though seems to be most common in Scandinavia and Germany.