I don't have a dog in this fight, but I think you should re-read this: data which cannot be easily obtained but can be obtained, e.g. through a torrent or on th

I don't have a dog in this fight, but I think you should re-read this: data which cannot be easily obtained but can be obtained, e.g. through a torrent or on the dark web. It's an extra piece of engineering to reliably scrape torrents and the dark web and exclude spam traps. "Easily obtained" is probably as much about this vs the copyright aspects. The person you are replying to is correct in saying that most people train on the "public web" (eg, common crawl data). The copyright implications of this haven't been tested in court as yet. It is worth noting that common-crawl data is widely distributed and would seem to raise the same issues you are identifying here.