So this is why new files weren’t showing up

Nothing like changing the default behavior of a program in a point release so that users then wonder why it’s not behaving as it should:

ownCloud 8.2 Release Notes

Changes in 8.2

filesystem_check_changes in config.php is set to 0 by default. This prevents unnecessary update checks and improves performance. If you are using external storage mounts such as NFS on a remote storage server, set this to 1 so that ownCloud will detect remote file changes.

Nearly all of the files on my ownCloud server are accessed from Samba shares on the same server; ownCloud is basically how I access my files away from home.  If it’s not monitoring filesystem changes, it will rapidly fall behind on which files have been created and deleted.

Until v8.1, it monitored filesystem changes in the default configuration.  I upgraded to v8.2 over the weekend, which no longer does that unless you add an option to the config file to reenable it.  Grr.