......nothing wrong with chip and oil roads......
You fail to consider loading. It all has to do with psi, pounds per square inch.
The psi’s exerted on the road surface from vehicle tires are transmitted downward in a cone of force. The peak of that cone and the greatest psi’s are on the surface. The chip and seal is thin,and transmits the load poorly. Asphalt concrete and Portland cement concrete are always thicker and able to better distribute that load to the subgrade and grade below.
If there is much heavy traffic from trucks or school busses the excess force will produce a rutted road. This is especially true of a gravel road with no subase and also for Tarmac and Macadam roads (chip n seal)
It was noted above there are portland cement concrete roads that are very old. In my experience they are mostly gone. The problem is expansion of the portland cement concrete. It moves and will crack unless there are expansion joints to contain the movement. On the interstate system there was great political and engineering design pressure to pave with portland cement concrete. Sadly, the lesson learned was that it is a mistake. The expansion joint pavement edges wear away and there can be vertical movement there resulting in a bone jarring ride whapata whapata whapata.
Asphalt concrete on the other hand is flexible and has good compressive strength. There is no need for expansion joints and the terribly disruptive and expensive maintenance.
For rural roads, maintenance becomes a matter of $$/vehicle trip. Low traffic count does not justify the expense of high traffic. The question for a politician is When do you draw the line?
In the end though, all roads fail with traffic and age.
I did not know that before. Thanks.