Hang on, the F-150 and Silverado started ballooning in the late 90s. The Hummer came, Nissan introduced their Titan truck in 2004, the Toyota Tundra got massive. All years before 2008.
Regulations may have well prevented reversal, but the buying public was clearly already making its preferences loud and clear.
Airbags, crash testing, NHTSA, fuel injection / data bussing, small changes to CAFE, comfort options, and emissions equipment all made vehicles get slightly larger, that’s true. But not “ballooning”.
The 2004 Nissan Titan you mentioned was smaller in every single dimension and aspect over its comparative 2004 Dodge Ram. That was Nissan trying to play big boy, but was nothing unusual.
I’m talking about everything. Take an entire line from a MFG and look at its model over model changes.
Find a vehicle that decreased in wheelbase. I wish you luck in your search.
There were more fuel restrictions for smaller cars after the CAFE amendment of the late aughts. Automakers were incentivized to build bigger cars to get around the restrictions.
Regulations may have well prevented reversal, but the buying public was clearly already making its preferences loud and clear.