Are you sure? NJB (in the vid several people have posted) postulates that it's the other way around: many US cities are basically Easy Mode for driving, with car-centric infrastructure, wide roads, few pedestrians and bikes compared to Europe, etc. The latter has kept way more of its old cities with their narrow, winding roads.
More dangerous how?
Also, no matter how much of a fan you are of public transport and trains, there is always the last mile problem, and roles that pretty much only cars can fulfill.