Skills do deteriorate with age, but not at the same rate for everyone. Some pilots begin their career with a higher level of capability and set of skills than others. Blanket statements don't apply to individual pilots.
One of my last flights as an airline captain was with an FO who couldn't enter a hold. I had to take the aircraft from an experienced, ex-USAF, four engine jet, aircraft commander. He didn't even have the grace to say goodbye or apologize for his display of ineptness, temporary or otherwise. He is still there and I have been gone from the airline's left seat for 10 years. That is only one of many similar stores. I know there is a limit, but I hadn't reached mine. I also recall flying with some captains when I was a young co-pilot who should have pursued another profession. Age was and is only a portion of the capability equation.
Now, 10 years later at age 70 I still fly a 747 and a DC-8 doing airborne science research, ironically for the same government that mandated airline pilots retire at age 60. I also fly my own 185, primarily in the backcountry.
Do I know my own limitations? Yes. Am I going to retire again? Yes, but on my own terms and not because of an arbitrary decision based solely on age alone. Meanwhile, I have the best hobby job on the planet that isn't motivated by Flyboy's insulting claim that older airline pilots have ex-wives to support.
As long as I meet the training standards, check standards and operational requirements, I have been allowed to fly. I enjoy it immensely and they enjoy the experience that I and others like me contribute to the operation. What concepts.
Sincere condolences to Eddie's friends and family. RIP