Because the population is growing where I am, if anything the roads are getting slower. Especially at rush hour!
Brightline has a solution for their planned LA to Vegas route. 96% of their planned high speed rail is in the I-15 highway median. (Source: https://www.brightlinewest.com/overview/project)
Yes, I know that won't work everywhere and there isn't always a highway median. I'm just pointing this out as one situation in which someone does have a (planned) solution to the problem of a highway already being there.
Also, we expand highways on a regular basis in the United States, and that often means demolishing things next to them. Perhaps there are alternative uses for that space?
"Safer than ever" is a hilarious claim given that cars have a much higher death rate than any form of public transportation:
