Yes but the weakest point is usually the trackers. If you shut down the trackers, no one is able to initiate a download. Except when you use a trackerless BitT

Yes but the weakest point is usually the trackers. If you shut down the trackers, no one is able to initiate a download. Except when you use a trackerless BitTorrent but even in DHT mode (for the trackerless torrent), you still need to connect to an initial server for fetching a swarm and have the initial view of the DHT network. In my view, we would need to improve the bootstrap process to avoid (or at least limit) the single entry point. But this is the classical chicken-egg dilemma...