Southern Californian suburbs are often "designed for pedestrians" in the sense that they have remarkably smooth sidewalks, with dips at curbs because legislation has long mandated disabled-friendly construction (in that sense the US is ahead of some EU countries). Of course there is the expectation that one should be driving, and it can get tiresome to wait forever at the constant button-operated pedestrian crossings, then have to rush across the six-lane road. But if people don’t walk, it is not due to lack of infastructure.

> But if people don’t walk, it is not due to lack of infastructure.

You can pave sidewalks, people don't walk because the grid of urban "space-time" is too spread apart to access anything by foot. It's not just because of lack of infrastructure sometimes, it's principally because most distances in a urban place with cars are car distances

Loads of Americans find themselves less than two miles from a shop or fast food location. That is a distance that many people in other countries will walk just to get outside and move, and think nothing of it. While in most of the USA sprawl is prohibitive, I suspect that, in many urban locations, people aren’t walking because they think it’s so very far. It’s not far, it’s just that a car and cheap fuel has already made many people lazy.

When people in population centers in other countries walk those distances they may weave from a store into another, along the way. Perhaps that's a reason those distances seem so very far in America, they're boring, visually barren and barren of things to do, there aren't street cafes where a friend or acquaintance might be found by chance.

Even though a suburbs sidewalk is just as "walkable" mechanically, it's much less fun. We don't want simply walkable streets, we don't want to think about walking at all. In modernity, health is an activity and consumer demographic onto itself. Seeing someone jogging in outfit has the air of class that a person simply walking to a destination doesn't have when we look at them, even though the person walking has healthy exercise figured, not as part of their lifestyle, but guaranteed in it.