Another issue is that over the last 10-20 years, probably a lot of people have moved out of cities to enjoy a better quality of living - from more internal space in a home to a garden etc. Work/Life balance is very much an important part of life, and if you're not well paid then city living can be a real drain financially and emotionally (think too about bringing up a family etc).
They could move because of the freedom afforded to them by a car. Some may commute by train once they've moved, but likely have to drive to a station as in many cases buses don't exist, did exist and were cut in the last 10 years, or have had hours of operation slashed. You might have a bus if you work very strict hours, but vary those and you'll either be too early for the first bus, or too late for the last. If one bus isn't available, you'll drive.
New build estates may be a lot further from a station than you could cycle (especially if it involves narrow NSL country roads), while some buses may be funded from S106 money for a certain period and disappear thereafter never to be seen again.
If one day we ever considered public transport to be essential and were willing to subsidise loss-leading services 'for the greater good' then we could potentially provide transportation that suits more people, but let's be honest - that's not likely to happen anytime soon, if ever. Another idea might be to surface public footpaths to make them usable for cycling, as there are a myriad of paths around me that I can walk or cycle for leisure - but once it rains, some are impassable without traipsing through mud and water - ruling out these shortcuts away from heavy vehicles.
So some people will always need a car, even if for not a lot of the time. They could potentially be the ideal customers for those sub-mini style EVs that companies from China can sell you for £4 or £5k (let's ignore for now crash safety etc- many are little more than an e-bike with a protective shell) and perhaps this is the ideal solution for some.. but we're not there yet.