Que faire des traitres ?
I hope at one point in the future Embark could add an option to separate betrayers from the other people. It's so easy to keep history of "team up ? yes ! then kill before end of game" patterns, and shadow-group them like cheaters are shadowbanned in other games.
Watching youtube videos and streams, I've started building a list of players that showed only betrayal behaviors (I know some watchers enjoy this kind of moments, it feels so sociopath). I'm not saying that I will remember all of them while i'm playing, but I'll try to match them via proxy chat, and if they offer to team up, i will probably kill them by principle, announcing in the proxy chat why I did it.