> Even if it prevents like ten deaths, the LiDAR will have paid for itself.

The statistical value of a human life (for US government purposes) is between 7 to 14 million USD depending on department etc. (Unless there's anything to do with nuclear, then it's pretty much infinity.)

I'm not quite sure how much LiDAR would cost extra?

Of course, in addition to lives saved, you have other benefits. Eg you can conceivably drive more aggressively and faster, when you have more scanners, because you can exploit more situations where a lesser system has to act conservative when it can't be quite sure.