It was used in Google translate, and BERT was incorporated into search in 2019, though I don't think it was a clear win for search, I feel like I started having to add exact quotes to everything technical/programming around then.
One thing I don't understand is google has so much metadata on search sessions to RLHF their search results.
E.g. when I start a search session to solve a programming problem (before llms), I will continually search different terms to get to my solution webpage. Then stop. This session metadata and the path I took is highly significant data that can be used to help llms recognise what research itself looks like.
Not RLHF, but my understanding was they heavily use that data and it was a big part of their moat, part of why competitors wanted to clone their results because they couldn't derive as good of quality from the web alone (Microsoft used the bing toolbar to clone them in the 2010s).
