Basically, it's end-to-end data engineering and analytics. And the more a company uses/invests into the platform, the more benefit and locked-in they are.
Here is the link for anyone interested: https://www.palantir.com/platforms/foundry/ and a YouTube explainer: https://www.youtube.com/watch?v=ZGGRCTTjLfQ
Given you've used it, just how self-service is it? To me this seems like such a large claim that - if it's doable - I'm surprised there are not more competitors in the "vertically integrated data providers" space.
https://en.wikipedia.org/wiki/Retrieval-augmented_generation
Basically, using your actual data/documents to supplement a general purpose LLM and generate better answers for your specific use case.
It is both very self service and not very self service. That's why they employ the FDE model from the article, to actually ingrain it into the client company to the point that it becomes self service.
It's extremely hard to build such a product from scratch and have it actually be good, that's why there's no competitors. Especially providing the finely grained security controls that the article talks about, and have the platform be secure. There's a reason their security team wins the biggest CTFs half the time.