It should not be about some blanket age ban, but about a competency basis. No matter what age any driver is.
I believe that EVERY driver should be required to pass an eyesight test at the very least at regular intervals and passing or failing will inform whether a licence should be renewed.
The comment about older drivers' reaction times being slower is true but their experience and years of reading the road I understand is superior to younger drivers who have not built up their experience.
I am approaching 70, an active member of the IAM (motorcycle branch), passing my advanced rider test about 5 years ago, and a frequent rider and driver.
I need a car to get to the many interests and commitments I have, eg a Lacemakers' group on the opposite side of the city, an Accordionists group who meet in another town (and the equipment for these 2 activities at least is not transportable by bus).
While I might have a bus pass, the city I live in is well known for its poor public transport system so using the bus for me isn't viable.
I had some concerns at one point about my physical fitness to use my motorcycle but daily gym attendance has addressed that - and I need a car to get to that! So no car would mean no gym, decreasing fitness and health and all the issues which would come with that.
So I'm afraid the 'everyone should surrender their license at 70/80/90' argument doesn't hold water for me.