That's quite a generalisation. People in major cities like London and Paris would obviously like to clean up the pollution and reduce the noise and disruption, but the simple fact is that the existing public transport systems are not even close to having enough capacity to replace private motor transport entirely, and there zero chance of them having it any time soon. And those are the ideal cases, where there is enough demand to make a reasonably efficient and close-to-24/7 public transport network viable. Those in smaller cities have much worse options in terms of efficiency, availability and reliability, as do those travelling between or outside the bigger cities.
You can't just ban cars to fix this, or price them off the roads with congestion charging or the equivalent. It would take a huge programme of investment in developing new mass transit alternatives and redesigning large parts of the overall transport infrastructure within cities to make forcible elimination of cars in favour of public transport a viable option, and any such plan would probably have to be implemented over a 50-100 year timescale, with those footing much of the bill never living to see the benefits. That's a tough sell for any political administration.
I personally think that making private transport less intrusive and damaging has far more potential to improve the situation in the short to medium term. Infrastructure for electric vehicles is one obvious move in the right direction, but more generally, our road systems are still designed around the idea that one person making a journey with limited cargo needs a car-sized vehicle, which is horribly wasteful in road space, parking space, fuel consumption, etc. We have some very basic infrastructure in cities these days for bikes and we make some allowances for motorbikes, but these modes of transport have serious downsides for a lot of people. Crucially, the changes needed to improve those downsides would also allow, for example, smaller electric vehicles that are still fully enclosed and having space for carrying small loads in addition to their human occupant. Combine that with increasing automation over the next couple of decades for better safety and general efficiency, and most of us might at least still be alive to see the benefits.