Imo, Naga Sadow and the hordes of Massassi Sith ghosts on Yavin-4 didn't jump the Rebel Alliance like Marka Ragnos did to Kyle Katarn (for no reason, mind you. mf just big and angry) bc on a spiritual level, Luthen Rael embodies the mentality of Post-Great Hyperspace War and Early Reconstituted Sith Empire Sith Purebloods more than Sidious ever did.
Like when the Republic spun back on the barely spacefarring Sith after Naga Sadow's Coruscant's attack flopped, they obliterated them. Shit was famine, mass suicides, civil conflicts, destruction of civilization, mass exoduses, loss of home planets, genocide etc. Lets be fr, the Republic did too much.
That brutalization and victimization is what birthed the Sith Empire and Sith Order as we know it.
If you a traumatized Sith Pureblood on Emperor Vitiate's fucked up fleet floating in space for 20 years after your whole family was maimed/killed when you was like nine, I'm sure that peace is a lie.
Tbh, the Sith Order of that era really seems more like a trauma response of a people who were victimized.
This societal PTSD is why the Sith Empire never had rebellions, like is you gon rebel to join the people who fucked your shit up? probably not.
Meanwhile, Sidious is to the citizens of the Galactic Empire what the Jedi and Republic were to the Purebloods. He's doing all the shit that the Sith experienced that led them to forming the Reconstituted Sith Empire.
Luthen Rael's monologue and the Sith Code are even similar. They both mantras of desperate and traumatized people who've been forced to give up everything in the hopes that future generations will be free from a oppressive force.
And you can be like "oh well the Jedi and Republic are good".
But imagine you a Sith Pureblood kid and your mom and siblings got blasted to pieces by a Republic starship canon all over some shit you didn't even know was going on, and none of you took part in. You don't perceive the Republic as good.
So, if you Naga Sadow and you see Luthen Rael's lil rebel gang on your exile planet, you probably gonna have more solidarity with him than Sidious. Sorry to my goat, but he spiritually has very little in common with the Sith Purebloods.
He's never had to give up peace in hopes of defeating an enemy that's killed and oppressed people around him. Yeah, the Sith are Sidious' special interest but what does he have in common with their lived experiences? Nothing.
And then Sidious is gonna take his Death Star to Naga Sadow's planet like dawg. That shit had to put him on every Pre-Bane Sith's shit list bc how tf you gon try to destroy the planet where Big OG Lord Sadow is buried. It's bad enough he in the daddy issue cult and not the real Sith Order lmao
tbh Naga Sadow was probably using his Battle Mediation from beyond the mf tomb to make sure Luke Skywalker shot that missile right into the Death Star's shit.