I know that qbittorrent has an option to do that in Tools > Options > Advanced > Network Interface. Transmission binds to 0.0.0.0 (all IPv4 interfaces) by default, it doesn’t bind to an interface just IPv4 address.
I wasn’t suggesting you did either, but the issue is when everything shares the same routing table and there needs to be certain exceptions for the thing to work, and you’re hamstrung by the exposed features of the OS.
We can tell how old accounts are obviously, and there are various threads spreading conspiracy rubbish, but I guess this is post-truth era after all where you don’t need proof of anything to make an accusation 
A good share of them don’t have any reasoning behind why they think we should do a particular thing though. None of them dug up Apple’s documentation or did any digging into why this happens beside it doesn’t with X provider that uses pf.
What in saying that crappy software kill switches aren’t really reliable? I don’t think anyone should disagree with that.