So, I just got into an argument that the OT hints at the Rule of Two that the Sith go by in the prequel era (not even necessarily the prequels themselves)…

Yeah, the series of films made before there was even a good understanding of the world it was building is hinting at a relatively obscure rule made by people (not even necessarily the same people!) 20 years later, and it wasn’t just the trope of the Dragon trying to pull a Starscream while the Master looks for someone more loyal to replace him. Riiiight…