But this is why I made my complexity statement in my other reply.
Why are firms sending around invoices, tables instead of parseable data. Oh I know the argument, because "so hard to cooperate" on standards, etc.
Madness.
Partly because the standards, such as X12, have a high startup cost to use them, they aren't very opinionated about the actual content, and you have to get the counterparty on board to use them.
What I mean by structured is: invoices, documents containing tables, etc.
Extracting useful data from fully unstructured content is very hard IMO and potentially above the capacity of LLMs (depending on your definition of "useful" and "unstructured")