The research is still ongoing, although perhaps lower-profile than what appears in the press.
RETRO did get press, but it was not the first retrieval model, and in fact was not SOTA when it got published; FiD was, which later evolved into Atlas[0], published a few months ago.
RETRO did get press, but it was not the first retrieval model, and in fact was not SOTA when it got published; FiD was, which later evolved into Atlas[0], published a few months ago.
[0]: https://github.com/facebookresearch/atlas