Each public housing authority is allowed to set a residency "preference" (not a residency requirement) but you're right, many of them don't seem to implement on

Each public housing authority is allowed to set a residency "preference" (not a residency requirement) but you're right, many of them don't seem to implement one. I assume that with the ridiculous limits on applying it has only become an issue in the last decade, at most. (E.g King County last opened their wait list for two weeks in 2020). Some places also implement a quasi-residential requirement by making the wait list open only/preferentially to people referred by a local service provider.