[squigz]

The metadata torrent is only ~200GB, which should be well within your capabilities.

https://annas-archive.li/torrents/spotify

Anyway, I think you should keep in mind 2 things:

1) 10,000 tracks really is not a lot. It sounds like a lot, but isn't. My own - relatively small - collection is nearly double that.

2) 10,000 tracks... out of 256,000,000 that AA archived.

I'd be very interested to see some more analysis done on this, particularly as it relates to, say, Last.fm statistics - but I suspect the missing music is not as significant as you think.

In any case, even if every one of those "niche" artists you list are missing from this collection, I don't think it's fair to say it's a "laughable attempt" - it's certainly better than nothing, even if it's not perfect.