As someone who spent 40 + years investigating motor vehicle accidents and the injuries resulting from them, I have to say something here.
Increased speed doesn’t just increase the number of accidents on a given stretch of highway, it simultaneously increases the number and severity of the injuries suffered by the occupants of the vehicles. Ask any OPP (Ontario Provincial Police) officer who has been doing highway accident investigation for years, or any similar individual anywhere in the world, and you’ll see that they agree with me.
In Ontario, as long as I can remember, most drivers have travelled at 10 km above the limit because police wouldn’t ticket you at that speed. Over the last 20 years or so this has been gradually increased to 20 km above, so what we’re talking about is an increase to an average speed of 130 km now, or as soon as people get used to it.
I’ve found that common in New York State as well, but not everywhere. I was pleasantly surprised to find on the expressways of Phoenix, Arizona, where the speed limit is 70 miles per hr (approx 110 km hr) at least half the vehicles were moving at 60 mph, as I did most of the time.
The problem in Ontario is not speed limits, it is traffic congestion from too many vehicles. Of course, this is automatically magnified when there is a collision, often due to too much speed for traffic conditions. If traffic has slowed to 50 kph, and someone is trying to get through it at 60 kph, by the usual means of frequent, often unsignalled, abrupt lane changes, the result is often an accident that brings everyone to a stop, for a prolonged period if there are serious injuries.
Although that situation is becoming increasingly common, increasing the speed limit is not going to remedy it, or anything else.
Of course, the dramatic in increase the cost of motor vehicles may eventually reduce the number of vehicles on our highways. You can only repair an old car so many times.Eventually it’s finished. So it could be that 20 years from now highways will only be for the affluent among us, who will fly along happily at higher and higher speeds.