Cars are rapidly going electric, silent, and intelligent. The first two improvements will remove the problems with pollution and noise. The idea that the production of an electric car produces a vast amount of waste and pollution is nonsense, big oil propaganda.
The added intelligence will provide benefits further down the road, some of which we don't even know yet. Once cars are smart it promises to radically improve safety, with smart cars able to avoid most accidents, drive drunk people home in the back seat, able to drop the owner at their office door and then find somewhere to park on their own, either in a more spaced-out area or an automated dense public garage.
Removing some roads and replacing with more shared/human-centric transport will make a huge difference to the utility of cities. We can do this independently of electrifying vehicles - see superblocks [1]
Trains already exist. They are proven technology. Smart cars have proven to be difficult to make safely. Smart cars will still be less efficient for moving lots of people than trains.
It's not just the cars. It's also the land use. All that extra pavement and other infrastructure for all the low-density land patterns cars necessitate is resource intensive to build and maintain.
This is just like lab grown meat. People think technology that will hit the market at a competitive price point in some indeterminate amount of time will save us from existential problems that are already manifesting. And that technological optimism is interfering with the development of the needed level of urgency.
Having paved roads means salting them in the winter. This has detrimental effects on rivers and wildlife.
I'm surprised we haven't had "ice mode" for EVs, you'd think they'd have enough computers where they could handle bad roads better.