Using 70 as a cut-off point comes from the early days of IQ testing when “moron” was a real classification of mental development. Apparently, being a “moron” was an adequate defense. Kind of like being a child, although more and more states are pushing the age limit lower for trying people as adults.
Maybe if keeping people in prison was less profitable, these things wouldn’t be discussed, let alone implemented.
We used to raise children as a community effort, with multiple generations involved. Grandparents were there to give advice and children grew up well-adjusted, contributing members of society. Nowadays we let psychologists screw the whole process up before the kid even has a chance.
Makes me want to cheer and set off fireworks.