[k_sh]

If roads were 20x wider, 68% of LA County would be streets.

Sure, turning two-thirds of a city into roads will cut down on traffic - but within realistic restraints on road construction, induced demand is real.

(There are 140mi^2 of roads now[0], and 4,058mi^2 of land mass[1].)

[0]: https://la.curbed.com/2015/11/30/9895842/how-much-parking-lo... [1]: https://en.wikipedia.org/wiki/Los_Angeles_County,_California

[ummonk]

Well there is a hypothetical world in which you could stack roads. It's prohibitively expensive, but not physically impossible.