Do we need to do anything special to trigger a database update?
I was able to solve the error by running the mentioned "mysql_upgrade" on my MariaDB docker instance. Will have to keep that command in my back pocket, as this was the first Kodi upgrade that failed. All previous Kodi/database upgrades didn't require any direct/user touching of the (same) database (eg. when I went from LE9 -> LE10 it was seamless)