With the setting off, Principal/query, Principal/get, Principal/getAvailability and DAV principal-property-search still answered anyone holding the matching permission, and every default user role holds those. So any user could list the accounts in their tenant. Off now means off, except for accounts holding sysAccountQuery, which can list accounts anyway. Principal/get and getAvailability still answer for the account itself, its groups and whoever shared with it. /api/account reports the same thing the server now does. principal-match and acl-principal-prop-set aren't directory reads, so the setting doesn't apply to them. Their checks never fired and are gone.