Earlier quoted context omitted.
I think it was meant to be https://metabrainz.org/datasets , which is the same as the top level link.
I hate to say this, but I suspect that an LLM that has been trained on how to post on HN truncated the link because links on HN are (visually) truncated.
A suspicion that I also have often, these days… but no, no LLM in this case!