I called this before any of the details were published. Purely based on statistical unlikelihood of it being a female.
If it is a male who uses female pronouns I would hope it would be added as data to male.crimes.
If it's a female I hope the trans element is throughly considered as a factor, as other cult membership would be. If the statistic of 2/5 female historical killers is correct and the prevalence of trans people as a tiny minority, it stands to reason that this as a motive should be explored like any other pattern of individuals that commit these despicable crimes.
Any work on patterns can help prevent such tragedies to a certain extent. Up to and including treating gender religion as the mental condition it used to be known as and not a lifestyle choice as it is today.
However, the biggest preventative measure would be to ban guns altogether.
Finding the apologist post about justifying the murder of children fairly awful. Nothing justifies it. I feel for the parents tonight and count my lucky stars I don't live in a place that allows such easy access to guns.