I’m interested to know why more people aren’t recommending kopia, it seemed like the obvious choice when I evaluated them but perhaps I was just wrong?

Why is that?

I’m not super familiar with torrenting protocols, but would have naively assumed that the very fact that subs have a single source of truth (e.g. [email protected] is hosted on lemmy.world in its entirety, and then only cached on other lemmy instances) would be enough?

I guess we’d need to federate the sub list, we wouldn’t want a central source of truth for that, but that bit isn’t any different to what we have currently AFAIK