Agreed poisoned is a good term. I’d like to see “version control” for conversations via the API and UI that lets you rollback to a previous place or clone from that spot into a new conversation. Even a typo or having to clarify a previous message skews the probabilities of future responses due to the accident.
This exists in Claude. Edit any previous message and it will fork the conversation.
"Forking" or "branching" (probably better received outside of SWEs) a conversation really ought to be a first class feature of ChatGPT et Al.