People need to retake tests after a certain age in order to keep driving
This is the case where I am in Australia. Can’t speak for all of Australia as driving requirements are not Federal but State based so it may not be the case in all States.
We get an eye test every time we need to renew license, 1,2 or 3 years (some people only have $ to pay for a year at a time) as standard. Then if you have been driving for a certain number of years and have not lost any points you can get a 5 year license (if you can pay for it) but you need to be under 50 for that. Even with a ‘clean’ record over 50 it’s 3 years at most.
Once people become elderly, forget the exact age (as I’m obviously not there yet🤣), then they need a doctor’s letter and test to retain their license. As you get older the frequency of this decreases to yearly. I seem to recall they need to foot the cost of this test as well, but I could be wrong about that bit.