I meant more like where would you get these data from? I guess the most precise would be to actually seed a bunch of torrents to different ratios and then test retrievability after X months.

Is it possible to obtain stats what seed ratio you need to get to on average for a torrent not to die?

this is true if you manually delete the txt file.

however, just unchecking it in the client doesn’t result in a broken seeder - at least transmission-gtk 4 will write the “file.txt” even if you didn’t check its box, or transmission will create a (sparse) “file.txt.part” file if there’s additional pieces to the “file.txt” that you didn’t download.

I would expect other clients to behave similarly.