If he were still alive, he would be writing and speaking about how such violence is unfortunate but ultimately acceptable— even necessary— to "preserve our freedoms", brushing it aside to be forgotten. He of course did so many times in life, notably in 2023 when he was quoted doing so in the media:
https://www.newsweek.com/charlie-kirk-says-gun-deaths-worth-...
Kirk's death has already overshadowed the news of that school shooting, which will indeed be forgotten by most long before we stop talking about him.
One final victory for Charlie Kirk, I guess.
He would have really advocated for violence, or school shootings? That seems odd. It is way different from "gun deaths are worth having the 2nd amendment".