[Martinjlm]

Originally Posted by bigd1276

It's all Administration driven.

On July 29, 2011, President Obama announced an agreement with thirteen large automakers to increase fuel economy to 54.5 miles per gallon for cars and light-duty trucks by model year 2025.

In early August 2018, the EPA and Department of Transportation, then operating under the Presidency of Donald Trump, issued a proposed ruling that, if enacted, would rollback some of the goals set in 2012 under President Obama. It proposed freezing the fuel economy goals to the 2021 target of 37 mpg, would halt requirements on the production of hybrid and electric cars, and would eliminate the legal waiver that allows states like California to set more stringent standards.

Upon taking office, the administration of President Biden stated an intention to set new fuel efficiency standards.[63] In August 2021 NHTSA released its Notice of Proposed Rulemaking offering new standards for the 2024–2026 model years.

The final rule covering the 2024–2026 model years was signed on March 31, 2022. Fuel economy targets for cars and light trucks each increase 8 percent for 2024 MY, 8 percent for 2025 MY, and 10 percent for 2026 MY. NHTSA projects that the updated targets lead to an industry-wide average of 49 MPG by the 2026 model year given a fleet mix of 48 percent passenger cars and 52 percent light trucks.

All of this is true, but GM had announced the intent to go 100% electric and to operate factories at zero net carbon emissions long before these changes to the rule making were finalized.