In Jun 2020 the (now sadly deceased) Bill Slawski (thanks again Bill for all your help) wrote a blog on a 2018 patent application r.e. ranking search results based on "information gain" scores.

This Google patent was aimed at addressing the problem "…when a set of documents is identified that share a topic, many of the documents may include similar information." and appears to relate to Google's Helpful Content update of 2022 ("part of a broader effort to ensure people see more original, helpful content written by people, for people, in search results").

See https://www.seolondonsurrey.co.uk/blog/googles-helpful-content-update-information-gain-scores for more information.