Every time I see someone explain why they need a car they always mention big grocery trips and often taking kids somewhere or other. It doesn't seem like driverless cars will do away with those, and if they're really so necessary, most cars available probably won't be lightweight and single occupancy.
I'm sure that there will still be plenty of multi-passenger cars.
But to your point, most people who drive trucks actually use the bed maybe a dozen times a year, and many people who have high occupancy vehicles take far more trips with only themselves or 1 additional passenger than they do fully loaded.
Single occupancy vehicles aren't practical for most people because they need a larger car some of the time, but if you don't own it you're free to request whatever vehicle you need right then.
Going to work by yourself--lightweight single occupancy. Picking up the kids--minivan.
