Every driver has the responsibility to drive no faster than conditions safely permit. That’s the Basic Speed Law. It doesn’t matter how fast cars can go relative to how fast they could when the road was built. The entire responsibility lies on the driver and not on the road.
As for volume of traffic, overcapacity usually results in lower collision rates with the possible exception of rear-enders.
No road is “dangerous” by reason of not accommodating reckless driving.
Ben don’t die on this hill. Some roads are dangerous. Some roads are oriented such that you come around a curve and get blinded by sunglare at certain times of the day/year.
You can’t anticipate that unless you are a regular on that road.
Some roads are improperly pitched and promote rollovers or skids under conditions where another road would not. These incorrect pitches are a matter of a few degrees and a driver would not be aware.
There are many factors that make up safe road design and older roads often do not meet the standards required of roads built today. If there were no unsafe roads we would not need the encyclopedic requirement rules that exist.
While personal responsibility is key and an excellent hallmark refusing to acknowledge that there are dangerous stretches of road is intransigence for it’s own sake.