In proper urban design that's actually a feature. People don't care about the posted speed limit - they probably won't even notice the sign. Instead they drive at the speed which they feel is appropriate for the road.
A lot of the suburban infrastructure in the US was developed around collision safety. This means wide roads and large setbacks, all in order to get rid of anything to collide with. However, this means that a regular residential street now feels extremely safe to drive: it's essentially a highway, so people will drive at highway speeds.
On the other hand, plenty of suburban road infrastructure in Europe has been explicitly designed to feel unsafe. The roads are intentionally made narrow, visibility is poor, and you'll run into plenty of obstacles like chicanes. Although plenty of that is a leftover from the pre-car era, it's nowadays an intentional design decision for new roads even when there is plenty of space. It's physically impossible to drive on those streets at highway speeds, so people are forced to slow down. Anyone with even the vaguest sense of self-preservation will drive a lot slower with a 6-inch clearance to oncoming traffic than with a 6-feet clearance. The lower speeds in turn actually make the roads safer, and make it possible to share them with cyclists and other low-speed traffic.
Fun fact: the narrowest residential street allowed in the US is wider than a highway lane in The Netherlands.
In proper urban design that's actually a feature. People don't care about the posted speed limit - they probably won't even notice the sign. Instead they drive at the speed which they feel is appropriate for the road.
A lot of the suburban infrastructure in the US was developed around collision safety. This means wide roads and large setbacks, all in order to get rid of anything to collide with. However, this means that a regular residential street now feels extremely safe to drive: it's essentially a highway, so people will drive at highway speeds.
On the other hand, plenty of suburban road infrastructure in Europe has been explicitly designed to feel unsafe. The roads are intentionally made narrow, visibility is poor, and you'll run into plenty of obstacles like chicanes. Although plenty of that is a leftover from the pre-car era, it's nowadays an intentional design decision for new roads even when there is plenty of space. It's physically impossible to drive on those streets at highway speeds, so people are forced to slow down. Anyone with even the vaguest sense of self-preservation will drive a lot slower with a 6-inch clearance to oncoming traffic than with a 6-feet clearance. The lower speeds in turn actually make the roads safer, and make it possible to share them with cyclists and other low-speed traffic.
Fun fact: the narrowest residential street allowed in the US is wider than a highway lane in The Netherlands.