Most of those firearm deaths aren’t school shootings. Sending your kid to play at a friend’s house where the parents have guns is a reasonable concern. Being afraid to send your kid to school every day because of a mass shooter is much less reasonable.
That’s a hard pass for me. I’d imagine the person who makes the decision about hiring you won’t even know if you’ve opted out because the data is gathered at the corporate level. But that’s just my guess.