In a Canadian context, on a two lane highway, sometimes doing the absolutely safe/totally cautious speed in a moderate snowstorm will result in a very large collection of vehicles behind you, with angry drivers. In particular if the persons collecting behind you are some combination of not very risk averse, commute on the same road every day, and are very confident in themselves because they have dedicated winter purpose studded snow/ice tires on.
Even if you also have good winter tires on, if your level of "caution" could be best measured as normal to high, sometimes it's a judgment call on when you want to pull off to the shoulder for 45 seconds to let a bunch of vehicles behind you pass. I'm not sure this is something any automated driver has been configured for. Or just generally to deal with driving when the road condition could best be described as "two only partially visible ruts in the snow where the tires of previous vehicles have driven, with snow in the centre".
Same thing in somewhere with a climate like upper Michigan or in Maine.
Turnouts exist. Unfortunately, head-of-line-blockers are very commonly already overwhelmed by the task of keeping tab of their own vehicle; would be a far stretch to expect them to simultaneously stay aware of traffic situations, spot the turnouts ahead, and then take the turnout.