Would a red light camera have saved her from a speeding car? No. Would a red light camera have stopped the speeding car from being a factor at all? Maybe.
Cars have to interact with pedestrians at some point. For every reckless act by a selfish driver that results in a child being murdered, there will be hundreds, thousands, maybe tens of thousands of similar reckless acts carried out by similarly selfish drivers that - purely by chance - don’t cause a child to be killed. If drivers were caught and punished acting like this the majority of the times it doesn’t result in a death, they’d be less likely to be in a position to slaughter pedestrians on the unlucky days in the first place.
Would a red light camera have saved her though?
What would have saved her: physical infrastructure that prevents cars from moving at dangerous speeds in areas where pedestrians are present.
Would a red light camera have saved her from a speeding car? No. Would a red light camera have stopped the speeding car from being a factor at all? Maybe.
Cars have to interact with pedestrians at some point. For every reckless act by a selfish driver that results in a child being murdered, there will be hundreds, thousands, maybe tens of thousands of similar reckless acts carried out by similarly selfish drivers that - purely by chance - don’t cause a child to be killed. If drivers were caught and punished acting like this the majority of the times it doesn’t result in a death, they’d be less likely to be in a position to slaughter pedestrians on the unlucky days in the first place.