I think you are showing that the tuning of AI models on just prompt and not a system message, as would be done on instructGPT completion models and initial ChatGPT, is predominantly 2021. My example screenshots alternating between between two months were a contrast between two system prompts.
Fun with AI: simulate early ChatML on -instruct tuning
Include “GPT-3” or “GPT-4” and you can flip the answering to 2020 or 2021 (just by AI pattern inference of GPT-2=2019).
(an AI model which was retuned on a subset set of RLHF and to make a stop token regardless.)