>Bittorent back in the day
What do you mean by this? Torrent never went away, there are countless high quality private trackers and even some really good public ones
But considering piracy + fediverse then DC++ was the most fediverse-y one https://en.wikipedia.org/wiki/DC%2B%2B You could connect to any given X server where you could share your local drive + chat with other users too. It's still really good to find some extremely niche stuff but torrent basically "won" because of the hash based seeding system (as in multiple user can share and peer the same stuff). DC was just seeing others' HDD and find whatever you can and directly download from there. But you didn't know that Joe's "Movie2012x264.mp4" and Jim's "Movie2012.mkv" are the same thing or different.