To ask which age you would expect this to happen?

[PandaWorld]

To become very deaf, tire extremely easily and have trouble with memory.
Would you say early sixties is too young ?

I turned 65 this week. My hearing is fine, I forget names sometimes but that's very common as we age, and I rarely take naps.

I doesn't sound like normal 60s issues to me, given that most people in their early 60s are still working.

Based on our family I would say mid 70's