Torrent doesn't magically find peers, even with DHT the torrent files have seed nodes baked in. A middelman required for both the centralized trackers and trackerless torrents.
DHT seed nodes are optional. A torrent node that's already connected to the DHT doesn't need them. Most torrent software has some default nodes baked in, from which it can discover the whole DHT.
Still dependent on centralized trackers. Same story with every useful package manager, there's always a middleman.