What laws and technologies would be more precise in the future?

Bad idea, Precision in the legal system is asking for trouble. As soon as you very precisely define some offense or another, it opens the door from someone to do something very similar (but not quite the same). And since the law would be (too) precise, the second bad guy could go free.

Better that we retain some wiggle room and ambiguity.

Speeding laws are actually changing to not ticket you unless you are doing X over the limit.

The precision on BS meters in the future will be much better. They need to be!

You won’t even worry about traffic speed in the future – your car will drive itself. The speed will be whatever is the optimal speed between point A and point B, depending on the traffic volume. You might be going 70.15 mph, then a few more cars merge on two miles ahead of you and everyone slows to 67.31 mph. You wouldn’t even notice.