Maybe I'm too old school, but I don't agree with you. Here in Belgium there used to be a law that when you have 2 lanes in the same direction with a middle section separating the other direction(s), you could go 120. Then it became 90, and now in most places it's 70. There are no pedestrians there, so there is no real reason why not to drive at least 90. Everybody there drives 90. Speed limits are currently just too low, that's why nobody is obeying them. And adapting roads to go slower is just plain ridiculous.

I have the feeling that the politics works like this: A lof of people are speeding on that road, so let's just lower the speed limit. Real consequence is that now everybody is speeding.

Same with construction works: 30km/h. Even in the weekend when nobody is working there. So basically a free road and you have to go 30km/h. Nobody does that of course. I know a buddy of mine once did that to be funny, and we got passed by a scooter. Huge line of cars behind us. Crazy.