Motorcycles are more a rule where we know they're unsafe but everyone riding one also knows that and takes the risk, there's not a similar broad carveout for cars/trucks until you get into the older vehicle imports I mentioned. Tractors are quite safe for the drivers and are allowed on roads because it's necessary to feed the country. Making broader cutouts just gives big holes for car companies to cut corners through the way SUVs mostly exist because they worm their way into light truck exemptions for certain rules.

I'd love to have something like an uncapped Kei truck available new but I'm also really reticent to just open up crash safety requirements for cars because it'll get used for a lot more than just the Kei trucks.