This is what I've found. It's so hard to do embeddings correctly, while it's so easy to search over a large corpus with a cheap LLM! Embeddings are also really inscrutable when they fail, whereas I find myself easily iterating if repogather fails to return the right group of files.

Of course, 'cheap' is relative -- on a large repository, embeddings are 99%+ cheaper than even gpt-4o-mini.