the value being extracted via LLM techniques is new value, which did not previously exist. The producer(s) of the old data had an asking price, which was taken by the LLM trainers. They cannot make the argument that since the LLM is producing new value, they should retroactively update their old asking price for their works.

They could update their asking price for any new works they produce. They also have the right to ask their works not be used for training, etc. But they cannot ask their old works to be paid for by the new uses in LLM in a retroactive way.