>Increase fuel economy -> Introduce fuel economy standards -> Economic cars practically phased out in favour of guzzling "trucks" that are exempt from fuel economy standards -> Worse fuel economy.

tl;dr: This is a myth.

There is no incentive to the consumer to purchase a vehicle with worse fuel economy.

There USED to be an incentive, 30-40 years ago.

It is not 1985 anymore.

The gas guzzler tax covers a range of fuel economies from 12.5 to 22.5 mpg.

It is practically impossible to design a car that gets less than 22.5 mpg.

The Dodge Challenger SRT Demon 170, with an 6.2 L 8 cylinder engine making ONE THOUSAND AND TWENTY FIVE horsepower is officially rated for 13 mpg but that's bullshit, it's Dodge juicing the numbers just so buyers can say "I paid fifty-four hundred bucks gas guzzler tax BAYBEE" and in real-world usage the Demon 170 is getting 25 mpg. Other examples of cars that cannot achieve 22.5 mpg are the BMW M2/M3/M4/M8, the Cadillac CT5, high-performance sports sedans for which the gas guzzler tax is a <5% price increase. ($5400 is 5% of the Demon 170 price, but 2-3% of what dealers are actually charging for it.)

The three most popular vehicles by sales volume in the United States are: 1. The Ford F-150, 2. The Chevy Silverado, and 3. The Dodge Ram 1500.

The most popular engine configuration for these vehicles is the ~3L V6. Not a V8. A V6.

Less than 1/4th of all pickup trucks are sold equipped with a V8.

According to fueleconomy.gov every single Ford, Chevrolet, and Ram full-size pickup with a V6 would pay no gas guzzler tax.

Most V8s would be close, perhaps an ECU flash away, to paying no gas guzzler tax. The only pickups that would qualify for a gas guzzler tax are the high-performance models-- single-digit percentages of the overall sales volume and at those prices the gas guzzler tax would not even factor into a buyer's decision.

People buy trucks, SUVs, and compact SUVs because they want them and can afford them.

Not because auto manufacturers phased out cars due to fuel economy standards. Not because consumers were "tricked" or "coerced". And certainly not because "the gubmint" messed things up.

They buy them because they WANT them.

The Toyota RAV4 is the 4th most popular car in the US. The Corolla is the 13th most popular. They are built on the same platform and dimensionally, the Corolla is actually very slightly larger except for height. They both come with the same general ballpark choices in engines. The gas guzzler tax only applies to the Corolla, but that doesn't matter because they both would be exempt. People don't freely choose the RAV4 over the Corolla because of fuel economy they buy it because the Corolla has 13 cubic feet of cargo capacity and the RAV4 has 70 cubic feet.

And before anyone says that the gas guzzler tax made passenger cars more expensive, passenger cars can be purchased for the same price adjusted for inflation they could be 50 years ago, but people don't want a Mitsubishi Mirage, which is the same price as a vintage VW Beetle (perennial cheapest new car from the 1960s) and better in every quantifiable metric, they want an SUV.

What may be true is that there is a national policy to keep fuel prices as low as possible, for a myriad of reasons, with one side effect of that policy being that it has enabled people to buy larger less fuel-efficient cars.

I do not believe it is auto manufacturers who are pushing for this policy. I believe it is the freight and logistic market. The auto market is valued at $4 billion, the freight and logistics market is $1,300 billion. GM and Ford are insignificant specks compared to the diesel and gasoline consumers of the freight and logistics firms (who have several powerful lobbies).

https://www.thetruthaboutcars.com/2017/08/v8-market-share-ju...

https://www.fueleconomy.gov

https://www.irs.gov/pub/irs-pdf/f6197.pdf (gas guzzler worksheet)