All these papers doing "research" on how to better prompt ChatGPT would be unpublishable then, given that API access to older models gets retired, so the findings of these papers can no longer be reproduced.

(I agree with you in principle; my example above is meant to show that standards for things such as reproducibility aren't easily defined. There are so many factors to consider.)

Well since you put "research" in quotes, I think you also agree that this type of work does not really belong in a quality journal with a high impact factor ;)

This, their training data doesn't even seem to be open either. So it's literally impossible to replicate their model. This makes me highly skeptical.