[screye]

The US did force [1] cars to be bigger, and everyone started buying bigger immediately.

[1] https://www.wired.com/story/the-us-wants-to-close-the-suv-lo...

If lanes are smaller, then people buy smaller cars. If parking spaces for compact cars are differently priced than that for huge cars, then people buy smaller cars. Set insurance minimums for liability by vehicle class. (scale it to liability damage statistics)

There are a lot of ways to strongly disincentivize big vehicles. If we merely start making them pay for the space they occupy, they immediately become too expensive.