Obama-era fuel regulations incentivized automakers to build bigger trucks:
One particular goal of the Obama Administration was to increase fuel efficiency through the typical political process: telling someone else to do it. To that end, the DOT and the EPA handed down a series of standards that nearly doubled the miles-per-gallon requirements for cars and light trucks.
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The new platform-based standards set fuel economy targets based on wheelbase and tread width, that is, how far apart the wheels are. If your vehicle is longer and wider, the fuel-economy targets shrinks. In the words of Dan Edmunds of Edumnds.com, “There was kind of an incentive to maybe stretch the wheelbase a couple of inches and set the tires maybe an inch [farther] apart, because you get a bigger platform and slightly smaller target.”
Proceduralism leading to unintended (or ‘unintended’) consequences; a tale as old as time.