A search engine's job is to rank the most relevant documents for a given query. A knowledge platform's job is to describe the world in a structured way so that a reader can navigate it.
The historical split
The web separated the two. Search engines indexed pages; knowledge platforms curated topics. Wikipedia is the best-known example of a knowledge platform on the open web.
Where they converge
Modern AI systems are collapsing the distinction. Retrieval-augmented models increasingly need structured knowledge to ground their answers. Products like KARADAVI sit on this seam: structured enough for machines, readable enough for humans.