I think that's a good point about driving being faster than other modes. When counting time lost to congestion, if it's still faster than other options, is it worth billions of dollars in freeway building to make it a couple minutes faster?

It's true that cars aren't going away anytime soon because we designed everything we've built since the 50's to be accessible only by car. But it doesn't need to be that way. 

We should have added cars to our set of tools and used them where they would be of the most benefit, but instead we recreated the entire idea of what a city is, and built everything to suit the needs of cars.  We've replaced what were easy trips to do on foot or by transit with trips that can only be done by car.

Older neighborhoods are very easy to get around by walking, biking, and can be served by transit very easily. All of Denver was easily traversed by streetcars in the early 1900's. 
It's the places that were designed for cars that make cars necessary.