Archive.org supports torrents for downloading huge files (i.e., >50gb archives of content) and the like.
You can probably debate endlessly piracy, ethics, "backups of media that have been purchased but have rotted away due to disc rot", etc. But fundamentally torrents are just a mechanism for delivery of large files or large sets of files, and they work extremely well for things in the tens-of-gigabytes range.
Installed ArchLinux from iso downloaded via BitTorrent just this weekend. BT is great for me because I live in Thailand and we don't always have the best mirrors but generally plenty of peers on fast domestic fibre links.
Yeah it makes me a bit sad.. torrents are technically really cool, and the casual anarchist in me likes how they remove the need for expensive infra/bandwidth to serve huge data.
Yet the overwhelming use by far is just to pirate vids.
People will use a technology for what it's best at. It's no different from how people use(d) Bitcoin mainly to buy drugs. BitTorrent is maybe slightly superior for legal file-sharing, but strongly superior for illegal one, and so it only dominates in the latter.
I don't think it's anything to be sad about; people use it because it works. It would be much sadder if it weren't used at all.
Shouldn't the casual anarchist in you rejoice at people hitting back on predatory, monopolistic, customer-hostile business practices of Big Movie though?
I occasionally use a torrent to simply move large files to a slow endpoint (essentially a 1:1 connection), so I don't have to keep the session alive for the whole file move. I know there are probably other, better, solutions for that, but it works for me.
You can probably debate endlessly piracy, ethics, "backups of media that have been purchased but have rotted away due to disc rot", etc. But fundamentally torrents are just a mechanism for delivery of large files or large sets of files, and they work extremely well for things in the tens-of-gigabytes range.