That … is definitely not how things work in the US. Municipalities set speed limits based on a variety of things including but not limited to maximizing revenue, the streets city council members live on, random news reports about speeds in adjacent jurisdictions, and so on.
Were a car to refuse to exceed the speed limit, it would be dangerously slow almost everywhere in the united states, arguably reducing safety substantially.
Were a car to refuse to exceed the speed limit, it would be dangerously slow almost everywhere in the united states, arguably reducing safety substantially.