As we age, mental and physical stamina decrease. It does of course vary by the individual. Also, we become more susceptable to a myriad of medical conditions which may not be detectable at the beginning of a four year term.
My next door neighbor is 92, mentally sharp, and physically fit for his age -- but I would not want anyone that age to bear the weight of all the responsibilities and critical decisions facing a president. For someone who really cares about the consequences for people in all walks of life , for the planet and future generations (which excludes Trump) the stress can exacerbate declining mental and physical stamina. During a global crisis or on the brink of war, a president may have to be up at all hours of the night making critical decisions.
I have great respect for Joe Biden, but was he fit for another term at the end of which he would be 86 years old? We're talking about an extremely demanding job which not only requires mental acuity with a broad base of knowledge, but being able to project sharpness and toughness in situations when all eyes are upon you -- inspiring confidence.
I don't think Joe had that at the end of his first term; certainly not to the extraordinary degree needed for the most powerful elected office on the planet. Ordinary is insufficient. Even for someone well ahead of the aging curve, is 90 too old? How about 100? Am I ageist if I say that's too old?
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