Kei Trucks & Cars

Your reasoning is lacking.

You're "forced" to go bigger, because car manufacturers are too greedy. The big pickups and SUVs are basically classified as commercial trucks, so the regulations are much looser when it comes to emissions and safety. Which make them cheaper to produce.

Car companies are more than capable of making powerful small cars under current regulations and even stricter ones, but that has a smaller profit margin. That's why they are fighting this, they want to keep their margins and not have to compete with these cars.