Does the BitTorrent protocol have an announcement / stored metadata of "recently highest percentage of file seen"?
This seems like one of the biggest problems with more decentralized torrents (i.e. ones not backed by a community / core seeder), but also most a UX issue and seemingly trivially solvable.
No, but clients do advertise how much of the torrent they have, so you can glance at your peer list and if you have 2 peers stuck at 10%... there's a good chance that you won't get more than 10%.
This seems like one of the biggest problems with more decentralized torrents (i.e. ones not backed by a community / core seeder), but also most a UX issue and seemingly trivially solvable.