[Retric]

Cars are terrible at scaling. The core problem is roads take a lot of surface area so adding traffic lanes reduces density which forces longer commutes. Add to that you need parking at both ends which reduces density further. http://streets.mn/wp-content/uploads/2014/09/car-vs-bike-vs-...

They are also worse for the environment and kill lot's of people.

PS: Cars also have huge direct and indirect subsides, consider who pays for your parking space while at work? Hypothetically in a major city ~2 * 100$ parking spaces + ~100$ insurance = ~300$ a month or 15$ per workday day even if your car, gas, and roads where free.

[waps]

You're absolutely right that cars don't scale well in theory, but when it comes to expanding capacity when that is necessary, cars outperform public transport. This is mostly because space is not often in short supply, but money always is.

Cars seem to have much better support for their expansion from governments, and that this results in better real-world scaling. It seems to me this is in no small part because car infrastructure is way cheaper per extra person of capacity than mass transit.

Both cars and mass-transit have huge subsidies, at least in Belgium.

[Retric]

Belgium has decent public transit and is below the point where cars have issues with scaling. It's really more an issue with sprawling mega city's where the suburbs can only expand in one direction. So ocean / mountains on one side, north and south huge city's so everyone is coming from one direction.