RDR2 is a good example. I'd forgotten about that. The level of historical accuracy in that game was truly incredible. It's really the best of Rockstar whereas GTA5 was (IMHO) the worst of Rockstar (and I loved the GTA3 games and GTA4). I'll be interested to see where GTA6 lands.

Deadwood was particularly good because it not only featured Pinkertons but painted them really well as the defenders of the wealthy and basically just a large and well-funded gang.