[D] how successful has RAG been in search/recommendation ranking?

There are some efforts to cast the retrieval/ranking problem as a document id generation problem, e.g., the différentiable search index papers 2 years ago from google and Microsoft. I am not entirely sure how worthwhile it is to replicate those systems despite their pretty bold claims of success. Furthermore given RAG has been wildly useful in chatbot, has any credible major effort been publicized or “launched” in the context of search/recommendation?

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