FWIW this is my go to source for the story: "The Real Reason Jaywalking Is A Crime (Adam Ruins Everything)" https://www.youtube.com/watch?v=vxopfjXkArM

It's brief and fairly entertaining.

Also, I believe the US Army wanted an interstate highway system to use in place of the rail network. So there were many stakeholders that brought us this car centric landscape into existence.