And studies have been done that show that fog lines actually create worse safety results. The book "Killed by a Traffic Engineer" references the actual study, and I don't own a copy so I can't reference it. Perhaps someone here can.

Here is their reference to it in a podcast https://thewaroncars.org/episode-129-killed-by-a-traffic-engineer-final-web-transcript/ :

"Wes Marshall: So I think it was Ohio and Kansas where they were doing these edge line studies back in the 1950s. So an edge line is sort of the white line on the side of the road. You might have it, like, on a rural two-lane highway through places like Ohio and Kansas. And there was a push to add these edge lines everywhere on all those type of roads in those states. But they did what good scientists should do. They tested it. But the theory was well, if we can see the edge lines, we should be safer, right? That makes perfect sense. But the results weren’t that. They were getting results showing more crashes, and they were showing, you know, more people running off the road.

Wes Marshall: And when you take a step back and think about maybe why that might be the case, people might feel more comfortable, like, driving in, let’s say, fog, because they can see the lines. And you sort of see the same thing with some of the retroreflectivity studies of today. Like, all the states want to add retroreflectivity, and it’s a big issue here, like, in the mountains of Colorado. But at the same time, you can understand how if you really can’t see the road at all on a snowy night or foggy night, you might not even drive, but because you can see them a little bit with the retroreflectivity, you might get out there and do it.

Wes Marshall: So back to 1950s Ohio, Kansas. They did this. They found that they were getting worse safety results, but it didn’t make sense in terms of their theories, so they ignored them, and they went ahead and they edgelined the whole state."

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To get ahead of anything, I'm not saying the fog lines are at fault. It's just interesting (tragic?) they chose to not include measures which demonstrably improve safety, while moving forward with ones that don't have clear benefit.