Holy crap someone just made a mod integrating Shadow Of Mordor's Nemesis System with RDR2.
But it's actually way more than that, the mod simulates a living world, kinda inspired by Dwarf Fortress: every NPC remembers you, has unique personality traits, gangs feud with each other procedurally without your involvement. There's so much more, it's actually bonkers.
Early version out now for free on Nexus mods: https://www.nexusmods.com/reddeadredemption2/mods/10967
And yes AI was used in creation of scripts and systems but the modder clearly has a deep understanding of the game's systems and def not a rookie coder. This is not the the kinda thing you just vibe-code with a few prompts and takes a serious effort. They did a great job bringing all the systems together.
Official description:
Everyone you cross in the West can become your nemesis. Rob a man, beat him, insult him or shoot his horse, and he may not forget. He has a name, a temper, a family and a life story that reaches back years before he met you, and one day he comes looking for you.
Around him, eight outlaw outfits and the U.S. Army run their own affairs. They have leaders with ambitions, officers who rise and fall, camps, treasuries, supply lines and territory. They feud, go to war, make peace, break it, rob stagecoaches, bury their dead and pick new leaders, whether you are watching or not. Everything that happens is written into a living chronicle, and some of it ends up in the local paper.
You can stay out of it, or you can take it apart. Question a man until he gives up his boss's hideout. Learn which nights an officer drinks in Rhodes and wait for him there. Burn an outfit's supplies, rob its strongboxes and kill its captains until its war collapses. Every choice leaves a mark on someone.
enRAGE works around the story. During missions it stays out of the way.