This is where your approach is all screwed up. Why are we going to reduce the amount of driving done, and design walkable living arrangements when we have all this wonderful technology like high-mileage vehicles and electric cars and hybrids?
You've got the cause and effect backwards. Suburbia(in America) did not succeed so greatly because of the automobile, but the automobile succeeded so greatly because of suburbia and the fact that the mass transit was torn down making the car into a necessity. Look at Japan where you live. There are plenty of cars, but no where near as many as America and your cities do not cater to them exclusively as America's cities do. Miles driven is much less as well. They look like they could use some improvements, yes, but unlike America, a car is not a necessity where you live, and thus people have the choice of whether or not they want to do without a car. Just look at the number of on-road cars per capita of Japan and compare it to America. Even if you were to eliminate the fuel costs, cars do not come cheap. In America, people often spend 1/3 of their incomes just to keep their cars going, not because they want to, but because it's difficult to find a job within walking or biking distance and our stores and other places of interest like schools are so far spread apart.
You seem to be saying that we need some self-control, but how likely is that?
As likely as any semblence of modern society is to survive peak oil. Adaptation or death. No one individual person or nation can change this outcome, but it will take a coordinated effort among everyone. So far the odds aren't looking too cheery.
It's like switching from Marlboro to Marlboro Light. We'll just keep smoking and still die of cancer.
It would be more akin to removing the addictive nicotine from the cigarettes altogether and maybe smoking once or twice a month as a social custom, if the hypothetical person in question would choose to smoke at all. Perhaps kill the laws and regulations and grow their own tobacco and make their own cigarettes while they're at it.
You have to get off the fence. You can't tout the wonders of efficient vehicles and the importance of car-free living at the same time. It's logically inconsistent.
This statement can be true or false depending on the mindset of the person in it is directed at and whether the one asking the question understands that mindset. It's not black and white, or only one single solution. It is using multiple solutions at the same time and having them compliment each other, instead of simply choosing one or two and discounting the rest of them. If the solution to the peak oil problem is viewed as a black and white issue, sure, you will find it logically inconsistent!