This is the strange/sad truth.

Clearly walkable neighbourhoods are highly desirable, and in the US people pay a massive premium to get them because they are so scarce. Yet, for some reason, new construction in the suburbs is all disconnected and almost never walkable.

There's a huge disconnect between what people want and what developers are actually building. The kind of density that leads to walkability seems to only occur in older and already expensive areas with infill development, never green field construction further from an existing city center.

Maybe it's impossible to build new walkable areas in the US.

Almost all actually-existing cities replaced less intense uses on the same land. They simply had the foresight to get this done before we recognized a community’s right to veto such changes. The next ones will not come until we have stopped recognizing it.