For some of us, for some types of data, huge amounts of RAM, or even privacy concerns, or even the occasional hallucinated answer, is an easier pill to swallow.
A recent example, maybe not the best example but recent, was the query "What do the three headed dog from the Harry Potter books and the cat from Alien have in common"
Paperless, DevonThink, even Calibre (the ebook manager) can do it.
You only need a day or two to categorize the documents. No need for huge amounts of RAM, or privacy concerns, or hallucinated answers.