As I write, our iCal feed page loads "None found" instead of the numerous current and future public events that are in active status on our Civi 5.13 (WordPress 5.1.1, PHP 7.2.13) site.
I don't see any WordPress Permissions settings that could hide our public events, especially not while I'm logged in as Admin.
I've disabled all WP plugins (except CiviCRM) and there was no change.
For what it may be worth, the Calendar (com.agiliway.civicalendar) extension works fine. But none of the feed buttons on the Events Dashboard deliver any current or future public events.
Also (thanks Aidan!), these buttons probably never worked on our site. If you're curious, the history of (and reason for now ditching) the workaround is detailed below in the Comments.
ALSO ... this from the Civi Log Viewer, and it coincides with loading the Events Dashboard in the Civi Admin. There are no log entries corresponding with loading the HTML listing of current and future public events.
[warning] Deprecated function CRM_Event_BAO_Event::checkPermission, use CRM_Event_BAO_Event::getAllPermissions. Array ( [civi.tag] => deprecated )
Nothing from the WordPress PHP error log. Where should I look next?