A search is a search. The architecture doesn't care if it's doing an vector search or a text search or a keyword search or a regex search, it's all the same. Deploying a RAG app means trying different search methods, or using multiple methods simultaneously or sequentially, to get the best performance for your corpus and use case.
> The architecture doesn't care
The architecture does care because latency, recall shape, and failure modes differ.
I don't know of any serious RAG deployments that don't use vectors. I'm referring to large scale systems, not hobby projects or small sites.
RAG means any kind of data lookup which improves LLM generation results. I work in this area and speak to tons of companies doing RAG and almost all these days have realised that hybrid approaches are way better than pure vector searches.
Standard understanding of RAG now is simply adding any data to the context to improve the result.