Let’s start with infrastructure.

Buses/metro/any public transit, barriered or not, sparsely or rarely exist. Even painted bike paths/walking paths, these usually exist ONLY in dense or older urban areas. You have either 1-1.5m wide sidewalk elevated 10cm or nothing separating you on foot from car traffic.

So that 250m is often on the shoulder of car lanes.

Now let’s talk property liability. You are responsible for injuries others sustain while on your property unless you have clearly posted signage expressing they were not allowed on your property. Even then and at best you’ll have to disrupt 6mo of your life tied up in courts+fees. (No right to roam. You do get the “perk” of open manhunting season on trespassers)

So that shortcut through the neighborhood where your neighbor laid out gravel because they care about community? Nope, that’s cyclone fence or cinder block wall. That alley between flats? Gated off.

It’s not even scale that’s the problem. You ALWAYS have to go around the ENTIRE block. A 250m Crow flight can easily be and most often is 1+km by foot, and only ever with a curb as your protection from traffic. You can’t safely get to geographically nearby places without putting yourself in mortal danger.

Also note European road design limits traffic in residential areas where the US grid system means every road is a main road and wide enough to promote excessive speeding.

Source: anecdotal/American living in EU