> It's a well-known fact.
It's a well-known fact that different people mature at different rates.
> You may also observe how prisons are full of young people.
The bulk of prison inmates are in their 30s and 40s:
https://www.bop.gov/about/statistics/statistics_inmate_age.j...
> Brains that are still developing are far more likely to make really stupid decisions without regard for consequences.
Then how come there are so many more 40 year olds in prison than 20 year olds?
> If I were to pick qualities for a driver, and had to choose between 'Makes good decisions' versus 'Faster reflexes', I'd pick the former any day.
But now we're back to experience, and you have to be allowed to do the thing before you can get that.
> Note that we don't let 12 year-olds drive. We have arbitrary age cutoffs that have nothing to do with quantifiable capability.
We do, but we shouldn't. If a 12-year-old can pass the driver's test then either that 12-year-old is competent to drive or your driver's test is inadequate in testing drivers.