I think it was driven by consumerism. People wanted stuff, and they wanted to impress. As long as they had the money and fuel was cheap, it was hard to talk people out of these things.

Some complexity was good, of course. A carburetor for example was a mechanical kludge that they used because it was good enough for the time. Improved fuel economy and reduced emissions essentially mandated that fuel injection be used instead.

There is tons of stuff in there to maintain the engine and all that. Computers, sensors, various systems of one sort or another. That in a sense is what drives the dream of all-electric cars. You can really strip an incredible amount of stuff out from under the hood and be left with a much simpler vehicle. In theory, of course.

I remember when I was a kid - cars with AC were a rarity (well we lived in Minnesota, but the summers still could get warm on some days)..

"For whatever reason, consumers have demanded bigger and bigger cars with more and more horsepower."

"for whatever reason"?? Could it have anything to do with advertising?

If you make a huge car you can sell it for more than you can a small car. The atuo industry had huge economic incentives to to make and sell bigger and bigger cars.

The report has many good, common sense ideas, but they miss certain factors about why we ended up with such a bizarre mismatch between efficiency and fuel economy. One is commonly known as Jevons Paradox--that increases in efficiency always (or at least have a strong tendency to) result in higher rates of consumption.

The other is the basic function of private, gasoline-powered automobiles. The main oil-based fuel needed to run industry and industrial ag is diesel. But once you've produced diesel from oil, you have a whole lot of leftover stuff. What do you do with it? Early on they hit on the solution of refining it into gasoline. But now you need a market for this lower-grade fuel. This is where the auto came in.

The central function of the private, gasoline-powered fleet of cars was to solve the economic problem of what to do with all that gasoline left over from the production of diesel. Bigger cars and gas-using trucks fulfill that function very well.