I would rather say that US cities are broken because of design, not for lack of it. Sure, standardizing signs, and requiring access to parks are top-down design. But nearly all beautiful European cities weren't planned, they have evolved. With individuals adding, and replacing homes and buildings over the centuries in such a way that footpaths were not blocked, and people could go from A to B easily, even if that meant that roads would not be at straight angles, wide, or at fixed intervals.

Besides the ubiquitous grid-pattern in the US, other regulation such as zoning, maximum building heights, plot-sizes, and parking lots, only made things worse.

(of course there is a lot of regulation now in Europe, and there even was some historically, and due to scale increase the market likely would not be able to build beautiful cities anymore (and I am normally quite skeptical of the unbound market) but in this case it might actually have worked at some time)

Pining for a European-style urban environment was one of the reasons I left California and went back to the 'good old UK'.