Earlier quoted context omitted.
BitTorrent is associated almost exclusively with piracy, and the protocol is actively blocked on many networks.
It also chokes networks - an open seeding torrent client significantly increases latency, even with the number of connections limited. It's a problem we have in my house with Spotify, which utilises P2P to lower costs - it has a negative effect on anyone else who is gaming.
Doesn't qos alleviate that, though?