Also, let's follow the logic to its conclusion
If having a brain functioning at its peak is a requirement of making important decisions, then it's probably more important to have a *maximum* age limit than a minimum. Because the older you are, the more your brain wears out
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Thanks to basic entropy, if you're at retirement age, your brain will likely be losing fluid intelligence, the ability to reason, solve problems etc.
Can you trust such people to make important decisions? If you insist and a peak-performance brain, then technically no
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