If you pay them enough money you can sign a custom contract with them that means you can sue them to pieces if they are later found to be storing your original content despite saying that they aren't.
Personally I've decided to trust them when they tell me they won't do that in their terms and conditions. My content isn't actually very valuable to them.
Context is not being stored in Gemini or OpenAi (yet, I think, not to that degree).
My one year’s worth of LLM chats isn’t actually stored anywhere yet and doesn’t have to be, and for the most part I’d want it to be portable.
I’d say this is probably something that needs to be legally protected asap.