What is design for single passenger cars? Most cars can fit 5 people and roads also carry buses, ambulances, and trucks that carry every single product* in the economy.
* Probably with the exception of coal and some mining materials.
So you agree that most cars are far larger and heavier than required? First search result for "average car occupancy"[1]:
> In 2022 the Average Number of Occupants Per Trip for Household Vehicles in the United States Was 1.5
This discrepancy is the reason for car pooling, ride-sharing, etc. (Note that Uber, Lyft, etc. are taxi services, not "ride sharing"; since the drivers themselves are not typically intending to travel the routes they drive)
> roads also carry buses
Yes, which is why cars should be removed from such roads, to avoid slowing down buses.
> ambulances
Emergency vehicles can drive in places where cars are forbidden (cycle paths, pedestrianised roads, etc.)
> trucks that carry every single product* in the economy.
Again, you're undermining your own argument: the subsidies given to private car infrastructure are so large, that freight companies exploiting that infrastructure can end up more cost-effective than those which use rail; despite rail being more efficient not only in terms of fuel, but also in terms of labour (since so many trucks would be required to do the job of a single freight train, and each of those trucks require a separate driver). Also note that heavier vehicles degrade the road infrastructure disproportionately; which is even more reason to reduce the number of trucks as far as possible.
What is design for single passenger cars? Most cars can fit 5 people and roads also carry buses, ambulances, and trucks that carry every single product* in the economy.
* Probably with the exception of coal and some mining materials.