I mean it makes sense. I’m not a psychologist but I have a psych minor.

I wouldn’t say it’s “important to child development”, as you can definitely get by without it. I’d say it’s more “beneficial”

It teaches kids the world isn’t sunshine and rainbows (which every kid should learn, but also while being taught that they can fix it). It tailors their sympathetic nervous response to be more moderate, which is definitely beneficial in the long run. It strengthens bonds between parent and child (if you “save” them from the scary thing). It gives them confidence to act during high stress situations.

If it’s not the parent being scary, I really don’t think it’s harmful. Children need to be exposed to scary things. I sure as hell was, and I have ZERO trauma and never have. Same with everyone I know.

Obviously there’s a line to draw, but this ain’t it.