Age can change how a task is done without removing the wish to do it.

Capacity and desire do not fade together. Someone may need to sit to do what they once did standing, or take a morning over what used to take an hour, and want it just as much as ever. Treating a change in method as a signal to take the task away removes something more important than the task.

Where you are tempted to step in, ask what would make the job possible rather than whether it should still be done. A stool, better light, a different tool, or a bit more time often answers it, and it leaves the work where it belongs.