I am all for personal autonomy on the principal of 'your rights end where my nose begins'. So long as you don't endanger or inconvenience other people, then you can do what you want: collect match-box cars, eat kimchi or read Harry Potter. I was recently deprecating thee idea that old people should be given carte blanche about when they would retire from a government job. Because that decision affects a lot of other people - the younger replacement, the patients/mistakes of an older doctor who has accumulated experience, yes; but also less dexterity, poorer eye-sight and slower reactions. In his 70s my father was diagnosed with late-onset diabetes which made him much more likely to fall asleep at the wheel. His children reckoned that was as good a way to go as any and weren't inclined to stop him. Then one of us imagined him falling asleep with a crocodile of primary school children just round a blind-corner. That imagined scenario opened up the mind to a wider view of our responsibility. We weren't forced to act upon our concerns because the old chap fell down the stairs and died [or possibly was terminated by "medical misadventure" - his hospital records were found to be missing] in hospital 4 days later.
My mother was a few years younger and not diabetic, and lives in a remote area of rural Dorset so she continued for several years to drive her car, which she called SS Independence, in and out of town. But in her mid-80s, her 3 year post-70 licence fell due and she called it a day. Luckily she had built up significant resources of social capital since she moved to the village 30 years ago. Anyone who needed a lift to town, or something picked up or had an appointment with the doctor knew where my mother lived. Before she became a pensioner, she spent years as a volunteer driver for Meal-on-Wheels. Now, having turned 97, she is the Oldest Inhabitant and a sort of mascot: someone will be available if she ever needs to get somewhere. My aged father-in-law Pat the Salt, in similar circumstances in a different country announced on his 85th birthday that a) he wasn't going to drive the car any more; b) nor was he going to mow the lawn. That's all rather commendable, where responsible elders threw in the towel before anyone was hurt. And I didn't mind mowing the lawn every other weekend in exchange for my dinner.
My Mum had a pal who confused the brake, accelerator and clutch while reversing in the recycling-centre; the old dear shot backwards across the hard-standing and whacked into two other cars. The police were understanding and struck a deal: she wouldn't have her day in court IF she agreed not to drive again. And it was so. The cost of running a car (which for most of us spends 23/24 hours each day parked somewhere) - insurance, tax, depreciation - is so astronomical that you can take a helluva lot of taxis in a year and still be ahead financially.
The story of Ben Brooks-Dutton's family has a less happy ending. His wife was whacked by an 85 y.o. who wasn't able to work out the difference between brake and accelerator pedals and died in a bloody mess on the sidewalk while Brooks-Dutton and his infant son looked on helplessly. The Perp was sentenced to 18 months in Christmas Week 2014 but that didn't bring the victims any satisfaction. Like a lot of people who suffer because 'mistakes were made' Brooks-Dutton didn't want the old chap to do time in chokey, he just wanted to prevent the same thing happening to anyone else. He has spent the last several years blogging about the situation in which he, and indeed the wider community, unwittingly finds himself. The Brits encourages people to grass up their elderly neighbours and family to the Driver and Vehicle Licensing Authority DVLA so that the driving license can be revoked. I guess you are expected to talk to your Mum or Dad first, before bringing in The Gumment to sort out the problem.
A lot of the responsibility is shuffled off onto the local doctor who is expected to tell their elderly patients that they are no longer safe behind the wheel. That would take rather a lot of backbone and the doc might well decide that, on balance, keeping the old fellow driving is the best option for him even if it increases the risk of unknown people. Cars promote self-sufficiency, social inclusion, efficient shopping, and a sense of freedom. But y'know a lot of the deficits of being deprived of personal wheels can be made up in a fully functioning community where people looked in on their elderly neighbours, helped with the shopping, fixed a dripping tap or replaced the light-bulb in the bathroom. There is a halfway house between caring for yourself and being cared for by The State. The support of your neighbours doesn't have to be monetised or bureaucratised. It's not original to me; it's called Adopt-a-Granny.