I know this has come up before, just still fuzzy on why it's a problem.
I can think of at least one.
Take someone like
@Jackluyt who is an active player and contributes a lot (
things like combat analysis and other videos). It happens that I have Jack as a neighbor in Felyndral. Jack is playing every day, but he is not playing that little city in Felyndral. That doesn't mean he doesn't use it. He might be logging in there every week to keep stats about how many players are participating in tournaments and how the top scorers compare across the servers. How are the devs supposed to decide that they should or shouldn't delete that city? If they do, they might just be forcing him to recreate it each time, until he gets irritated enough to just stop playing. Or he might just have created that account to look at one thing, and only logs into it by accident once a month, or less. They don't know what he's thinking, or if he cares about that city.
They might be able to overcome that by allowing us to observe information on other servers, and look up people without having a city, but that's a bunch more programming that is probably (for the moment) better used in other ways. An easier choice might be a settings check-mark "Flag my city for deletion if I don't log in monthly."
It's easy to tell when an account is inactive, but it's not so easy to tell when a city attached to an active account should be removed.