Privacy is the key
It is all about behaviour. Private car drivers choose their own car for the daily trips even if most of them have other transportation alternatives, often at a lower cost.
The future of sustainable mobility is Autonomous, Connected, Electric, Shared.
But sharing rides with strangers, in a small vehicle without a driver, every day may not be attractive enough compared with the private car to change the beaviour. And then we still will have a heavy traffic with people commuting in their fossil fuel cars for many years ahead.