Because I like to run it on my NAS, I despise the embedded SQLite and always want it to use MySQL instead. This has always been well-documented in the slimdevices wiki.
When these steps are applied to Logitech Media Server, it reverts to SQLite on it's own.
After some troubleshooting i found updated instructions here. For the tl;dr folks, here's the relevant lines to server.prefs:
dbtype: MySQLI can't wait to see how they will name v8 - and how they'll change the config settings once more. Sigh.