In other words, if trainees are dying that means civilians will die as well.
Consider it from an evolutionary perspective: a pinned animal is a dead animal. So we should expect animals to resist being trapped to the point of killing themselves / dying from the stress of fighting to break free. It's well known to be true for many animals and its also true for humans.
Anytime a person is forcefully restrained there is a risk of death.
Knowing that people get into this instinctual "fight" mode frequently during police encounters, to the point where they'll exert themselves to the point of exhaustion and beyond, I do wish police had a greater duty of care standard to check on people and assess for medical emergencies during such scuffles.
Indeed. And we should treat forceful restraint as a potentially lethal move-- since we know from the statistics that it is-- and emphasize using other approaches where possible.