OK, here’s the deal.
As an octogenarian who hangs out with other octogenarians, I can speak from personal knowledge of the “memory” issue. We all or at least many of us have issues with not being able to correctly call up a name or word at will.
The name is there in memory, the memory is not lost, the problem is instant recall. That is at any given moment, the name of my good friend’s wife can not be instantly recalled. After an interval, it will pop up.
The hard drive is full and access to files not in constant use takes a while.
Should a person with severe loss of recall ability be President of the United States. Probably not.
You described the 80 year old mind perfectly. In my 80th year I’m experiencing exactly the same. At least the effect has not disturbed my critical thinking. My aunt worked until 85 with mental acuity sharp. It was her eyesight that led her to retire. Her memory started to regress a bit at 95 when she complained that she could not remember where she left her checkbook.