Support contacted with this:
I have been away pretty much a good part of a year. When I returned a few days ago I didn't see it, but today I did. Some of my ring 3 to 6 cities that I scouted a long, long time a go have been un-scouted. Is this a "game feature" or what? The outer scouting...
I do think you are right that higher up players may find space at a premium...but not everybody plays for the guest race/tech tree. Some do, in fact, play for the aesthetics. And they would, no doubt, get more enjoyment out of using the space for beauty than progress. In any case those who...