I am glad the article mentions CAFE standards. Government CAFE regulations are the primary reason vehicles like Trucks and SUVs have gotten so much larger in recent years, and almost no one talks about it when these conversations come up.

Simply put, CAFE standards were modified to include a vehicle "footprint" measured in square feet in addition to vehicle weight. The larger the footprint, the lower the fuel efficiency standards for the vehicle. The intent was to give a break to heavy work trucks that needed more powerful engines, while still forcing passenger cars to be more efficient. The unintended consequence was that automakers now had a loophole to sidestep stricter emissions standards: just make the vehicle larger and heavier.

This is a good article on the subject, with graphs on the CAFE fuel efficiency target curves in it (scroll down a bit to see them):

https://www.greencarreports.com/news/1111946_for-pickup-truc...