"Many" is doing a lot of work in your claim.
I recently moved to Houston where it feels like every road is a six lane stroad. If transportation were reduced to mass transit, bike lanes, and commercial transit like deliveries, how many of those roads would we need?
- 1 or 2 car lanes (each way)
- a tram line (one each way on each side of the street, or in the middle)
- a separated, 2 way bike lane on either side of the street
- a separated (from the bike lane) sidewalk
- a canal
As you can imagine, this takes up a lot of space. Despite this, things feel much more walkable. The reason? No enormous parking lots around every store. Parking is generally almost entirely done at P+R parking lots outside of town, then taking public transit in.
You can walk from your home to a cafe or corner shop for fresh produce almost everywhere I lived in Mexico.
Not until I moved back to the US did I remember how us sad Americans (or at least Texans) have to pile into a car just to drive to a cafe, though inside the city/suburbs this is also caused by zoning laws.
Granted, I'm just ranting. But I forgot how bad it was. Fortunately, some of this is very slowly changing. Even Houston is laying down more bike paths: https://houstonbikeplan.org/houston-bike-plan-map/
> In addition those 6-lane highways are all toll roads
6-lane means total lanes, so 3-4 in each direction like Richmond Ave or Westheimer Rd in Houston which you have to take just to get to the gym or grocery store.
But I think you need to go to Houston on Google Maps and look at all of the freeways that are 5-6 lanes in each direction bursting out like tentacles from the center in all directions. It seems like you're not aware that these exist?