Another lesson is to obey authority unquestioningly or it will lead to disaster.
Yet elsewhere in Last Jedi, heroic sacrifice is seen as foolish
But it sets a standard The Last Jedi doesn't necessarily live up to sometimes.
I could look up the name on Wookieepedia but I refuse to.
A mirror.
Plus they literally set a shrine on fire.
Some people were always going to reject it.
It's also a film with a sideplot where Chewbacca is annoyed by cute CG penguins, who inevitably grow on him.