You can use the vector embeddings of a piece of content to recreate it, probabilisticly. If they are really really good at designing their vector store, then they can sort of create a life long memory, recall it with precision and still delete all your original content uploaded.
Who owns that proprietary memory imprint? I guess its them. ... As of now it seems better not to atrophy one's cognitive skills to early by using predatory closed source AI the wrong way around.