Drunk Driving is weird: one can do it *without harming anyone*, effectively doing the same action as someone driving legally, and it was still illegal. Distracted driving is similar.
I *hate* drunk driving: its horrendous risk management, and easily avoidable with a small amount of planning ahead. (I also dislike any policies that encourage drunk driving, like hassling or ticketing people sleeping it off in their cars or that left their cars behind)
I also don’t like the idea of criminalizing behavior that is just risky. It seems too close to “we don’t like possible consequences of what you’re doing, so even if you get really good at it, we as a society prohibit you from doing it.”
Driving just over the legal limit of intoxication, on average, makes you slightly over 100 times more likely to get into a car accident than if you were sober. You’re also more likely to be seriously or fatally injured, although that statistic is iffy as we don’t have great data on the actual rate of drunk driving (tracking illegal behavior is hard).
I don’t know where the “too risky to be legal” line is. I’m worried about making things like that illegal. The “100 times more risky than conventional behavior” feels pretty safely in the “this is more than enough additional risk to make illegal” area. Especially when a large portion of our fatal accidents are already driving related.