and the acceleration of a collision is measured in split seconds, so the acceleration is going to be way higher than your velocity suggests.

As pointed out already, acceleration here is massive, as collision takes split seconds.

A more useful formula is: F=m*∆V^2 /2, where F is the force, m is mass, ∆V is speed difference (essentially your entire speed if you're gonna hit the wall, and that's very likely).

Notice that speed in this formula is squared, so doubling the speed results in four times the impact.

22% higher speed leads to 50% higher impact.

41% higher speed doubles the impact energy.

Etc. etc.

Also, mass of your car, even though it's not squared, impacts the result greatly. Twice as heavy car will exert twice the energy at the same speed.

Sure. But speeding doesn't cause collisons nearly to the level of any of the other things.

Going slow is a great way to reduce damage once a collision has occurred. Artificially slowing down roads (by throwing up a camera and a sign and nothing more) doesn't do shit to prevent collisions in the first place. It might slow down the road. It might make someone panic and jump on their brakes to avoid a ticket. It might get people paying closer attention to their speedometer than to the crosswalk up ahead.

Put another way, you're referencing the second law. Second law doesn't matter until the first law is broke. Don't act upon an object, won't be no actions upon another object.