I was not talking about city streets. And it doesn't matter. How long do you think does it take for a car to go to a highway?

It doesn't take to long is still much cheaper.

In munich you have a autobahn/cityring in the city. It takes perhaps 20 Minutes in city traffic to get onto the autobahn / highway.

There is a reason why we have only underground trains and why it takes years to build a new tunnel for them.

Also having the city traffic more autonomous would increase the traffic flow.