The real question is, how do we permanently kill the fanatic?

You have to treat the idea of the Scorn like you would typical zombies. They're essentially undead that are raised by a commanding lich (which is Fikrul). First the undead are made from the remains of corpses (normal fallen) which become scorn. From then on, the zombies can be altered or deteriorate as they're used in battle. Most scorn turn into the types with guns and armor when first resurrected. Ressurecting them a few too many times and they turn into screebs (essentially just balls of ether). Alter a scorn a few times and you can 'upgrade it' into a abomination. Eventually the body goes past its limit and just... dissolves (most likely after the screeb stage). At that point, the corpse is no more and thus cannot be raised. Death by incineration or explosion (which destroys the body) would end they cycle of resurrection very quickly. In regards to the Barons, I'd imagine they 'can' be resurrected several times (as seen by the Mechanist PE), however, most of the Barons are killed in ways where they're incapable of being revived. Bomber explodes. Sniper is trapped deep in hive territory. The Mindbender dies a 'true death' in his pseudo ascendant realm. Trickster could probably be revived. Rider explodes. It's also likely that resurrecting a Baron may have adverse effects... meaning that even if say, the Trickster, was resurrected it may no longer be 'the Trickster' anymore... but simply a dumber, more disjointed body that once was the Trickster.

... We used bullets, and rockets, and one time i used a sword... [spoiler]not included in the DLC[/spoiler]

Fanatic can only resurrect them if he has something to resurrect. Fanatic himself is immortal, and can use Dark Magic to resurrect Fallen or Scorn at a cost. That cost is that he can only stitch them back together, so that mean constant resurrections turn them into Skreebs, which just explode and die for good. Which explains the Barons deaths. Mindbender was lost in his Throne World. Mad Bomber and Trickster were disintegrated due to his bombs. The Rider was probably dissolved in the acid and the Hangman burned. The Rifleman was probably eaten by the Hive. The Machinist was the only one that was left intact, so that's why there is the Heroic Public Event with her.

It is unclear how much atonamy the Scorn have. The Fanatic gets a pass because I guess he's the source of Dark Ether, but maybe he [i]could[/i] bring the Barons back but they would be mindless slaves with no personality.

Technically the Fanatic is the one that just somehow comes back to life. He then can revive the other ones. If you pay attention to the Hallow Lair strike we don't know how he came back but he is back and we go to kill him again. He's like the only strike boss with a lore reason for us to keep killing him repeatedly. Just like Riven is the only one with a real lore reason for why we fight it so many times (dreaming city 3 week wish cycle hacks).

Sleeper Simulant mostly

I’m sure they could all res. You can still summon the machinist on heroic ritual and then there’s the hallowed lair strike. Another inconvenience to their “evolving world” concept. Even the devil splicers had their own raid, ah well

I still refuse to believe they're actually dead Fikrul comes back all the time The mechaniste is rezed for every heroic dark either ritual And one of the screens in D2 said "aid the Spider with the scorn Barons when the tangled shore becomes the flashpoint"

Do we really ever kill anything in Destiny? I mean, we can do the Thousand Voices strike 2000 times, and there will still be a Xol to kill on the 2001st.

I lured them in with a sign that said "Free bird seed". Above the pile of seeds on the road was an Anvil tied to a rope. If by chance they escaped that devious trap, I was laying in wait with a rocket strapped to my back and a pair of roller skates. They would never be able to outrun me. Worked like a charm. Didnt even have to resort to painting a fake tunnel on a solid wall they would crash into

I say throw their bodies into Sector 6 where the SIVA outbreak is. Maybe the Fanatic will be dumb and try to recover their bodies in Sector 6 and get infected by SIVA. BOOM next raid boss.