I think it's a side-effect of getting old. People find driving harder, even if they used to do it intensively.
It is a common side effect though. My 82 year old friend is now having trouble using the same computer she used effortlessly only a couple years ago. It takes her more time to remember the appropriate action to accomplish the required task. Sometimes she forgets a crucial step in a necessary sequence. She's otherwise pretty well as competent mentally as five years ago.
I suspect that the real danger is that the generation(s) that grew up with console gaming are about to enter the retirement homes and I predict there will be lots of injuries like broken hip and collar bones as a result of fights over whose turn it is and who is taking too long a turn on the XBox.