Try this when you are in your 70's and come back and we'll chat.
70+ year olds cycle all the time here in the Netherlands. My parents included. Most use e-bikes nowadays. I suspect more elderly cycle than drive a car, driving requires much faster reflexes and the potential for accidents is much higher.
And bring a cure for my chronically poor balance on your way over.
Here you go. Again super common among the elderly over here.
Many 70+ yr olds cannot or should not be driving cars either, because of eyesight/reflexes. Bicycles on the other hand, especially if conditioned throughout life, and later Trikes/Handbikes/Recumbents can be great options for many elders, and cycle infrastructure is perfectly usable for mobility scooters etc for those who really can't or do not want to bike.