Never a simple solution.
It sounds like it is more of a question of organizational culture than sound practice.
There are some important things to consider.
First as always, seen safety. In some places, calling a pt dead on scene is a really bad idea. (as in a threat to your life and health.)
If that is the case, scoop that corpse into the ambulance and make your way out of there.
But recognize that when you bring a corpse to the ED, it takes up resources and generates a bill. (a big one)
So in the interest of survivors, if the patient is dead, call them dead and let the grieving process start without another heavy financial blow.
Resuscitation in the back of a moving vehicle really doesn't lend to effect CPR, so with the exceptions of scene safety and penetrating trauma, it is just an unjustifyable risk to the providers and bystanders.
If you can work it to the end and call it on scene (by whatever method your agency demands) it is a much better choice.
No exceptions for kids. If a kid has decompensated to dead, with the exceptions of maybe penetrating trauma (a very long shot) or cold water immersion (more realistic) that kid is not coming back.
Again, providing false hope and an even larger bill takes a toll on survivors. In some instances it can break up families and put people on the street.
In a stressful event like a loved one arrested, the calm logic of an EMS provider is much more beneficial to all than an emotional decision.
If you are not aware, if you do not transport, then you likely will not be paid anything. This is something many US EMS agencies wrestle with. So there may be some downward pressure because of the economics of it.
The other issues are the relatively unconfident or incompetent provider. I have noticed providers who are not experienced or well educated tend to be rather equally emotional as distraught family.
"Brave are those who face great challenges, braver still are those who face the unknown."
In fairness it is not their fault. During stress they revert to what is comfortable, and let's face it, when you are uncomfortable with a patient, the number one strategy in medicine is to punt on first down.
Doctors do it all the time, how could you expect anything different from EMS providers?
Working in a medical capacity (even a physician extender) requires that sometimes you must report unpleasant news. An amateur attitude runs/hides, a professional attitude steps up to the plate and does what needs to be done.