[throwaway2037]

I did more research on this matter and found a this PDF: https://dor.georgia.gov/document/document/policy-bulletin-mv...

    > Kei Vehicles are not compliant with U.S. Federal Motor Vehicle Safety Standards (FMVSS). Therefore, they are not “street legal.” Kei Vehicles are barred from titling and registration.

I found other sources on Google saying you can cheat this rule by finding a state that does not strictly enforce FMVSS rules for titling and registration. Then, you can (illegally) drive the kei truck in another state. To be clear: This is illegal, but you need to be caught. Also, it looks like there are auto body shops that will modify a kei truck/car to make it street legal. I have a seen a bunch of YouTubers driving kei trucks/cars with California license plates. Thus, I assume the work was done to make them street legal.

Thus, we can conclude that FMVSS prevents a race-to-the-bottom in vehicular safety for cars in the US. Honestly, I expect all highly developed nations to have similar rules. Why? For the safety of children, more than anything. Even if a parent wants to drive an unsafe car, most societies will prioritise the safety of child passengers over the "liberty" of the parent/owner/driver.