I think that''s just simple courtesy which we could all use. I try to move over if a single person is behind me (unless perhaps I'm heading into a turn or situation where it's blind)
As much as I'm for simple courtesy.....I can still be a bit of a prick. I live on a small, dead end road. Only 5 houses here so everyone knows everyone. On a lake with some public property so we get outside visitors here. Road is about 12' wide. I drove a Miata for a dozen years and going down the road, someone (non-local) would be coming down the middle of the road in their truck....forcing me to pull off into the ditch. In some areas, the ditch doesn't exist and it's actually an embankment to the water. They usually don't slow down very much either.
General thought seems to be size makes right....so the little guy (me in the Miata) has to bow to the larger trucks.
Well.... our property borders about 30% of the length of this road. When I'm out in my industrial backhoe with an 8' wide bucket, there is no room for two to pass at same time. Interestingly, when one of these punk drivers comes down the road, they are in the middle of road again and now we have an impasse.... I just stop. They stop as they are expecting me to move over for them.
What they don't understand is I'm tired of their attitude and now, I'm in the bigger machine.... so I just sit. I'm essentially at home so I have allllllllllll day to sit. We sit & stare for a minute before it finally sinks in their thick skulls that I'm not moving and they can't get past me.... and I force them to backup however far they need to backup to turn around.
(since it's a dead end road and I live at the end, they have no real reason to continue further.... so I know they're just out exploring)
I would have never copped that kind of attitude had I not spent 10 years or so being pushed around and off the pavement by them. Now, I'm happy to play their stupid game because I win.