[OP of "The younger the victim, the less it should matter"]
What's the big deal if their children are killed in younger aged schools? Which is worse resources wasted? Elementary school kid or a college school kid? Adam Lanza might have killed some elementary school kids, and that sucks that the resources spent on them were wasted, but those foids could always make some more. This is in contrast to high school and university when it's about 20 years of investment down the drain. I'd be soo pissed.
Now let's look at foids who are killing their own kids with abortions. I think the main issue with school shooters that foids have is that the foids didn't get to kill their own kids. Foids abuse their children so much through indoctrination and sending them off to places to be bullied. It's neglect. A foid would rather get pregnant and have an abortion just to feel like a god over life.