Stranger kidnapping is an extreme black swan, but there’s plenty of more realistic scenarios where tracking could mitigate a bad outcome. Kid gets off the school bus at the wrong stop: found in minutes. Kid is riding bike, falls and knocked out: found easily.

There’s a ton of rare, negative scenarios where risk reduction is so cheap and easy that you’re silly not to do it. Car accident deaths are about 1 in 100 million miles driven, you certainly can’t control other drivers, but not putting on a seatbelt is stupid.