Cities old enough they were designed for foot-traffic, not car-traffic; modern-ish train systems and other public transit; the high price of fuel... My guess is less need.
And yes, less need as well.
We used to use hire cars for special trips and use public transport for other things (for a time having no vehicle by choice); then we got a scooter (as a couple) to help with going out and doing shopping trips and such (definitely cheaper than getting taxis).
Then work necessitated having a van, once you have a vehicle then it's only ever cheaper [where I am] to use public transport for long trips for an individual - once a couple or more travel together it's cheaper in a car (including a proportion allowed for road tax, ongoing license costs, depreciation, repairs and petrol [using Gov mileage allowances; not including learning to drive!]).
Problem is, as with many things when you're poorer, the upfront costs for a car mean that those less well off can be barred from ownership and so barred from the per-mile savings and convenience.
Having a car for our family now means I can't afford to take the bus and watching near empty buses go past as you walk home in the dark, cold and wet, isn't much fun ...
Scrap values being high has pushed the price of the lowest costs second-hand cars up a bit. Not so long ago I had to pay to have a still usable car scrapped to avoid paying the license fee. Bangers then were essentially free.
Worth cycling home from work?