"Roads in the US are too straight and too wide to force drivers to be more deliberate in how they drive."

I guess it depends. Most pedestrians are in cities or towns. The roads there may be straight, but not necessarily wide.

I'm also not sure how a road being straight and wide is a negative. Making them more narrow and winding is arguably less safe. Even if people reduce their speed, you present new issues of reduced line of sight, decreasing available reaction time. You also have reduced performance (braking on a turn vs straight).

Many areas do have some speed bumps. Mostly these are residential or near crosswalks.