We have ragdolls and physics joints, someone just needs to integrate them, some people already did. The GMK kit has ragdolls, I think, I saw them live in action. There is also a resource for hitboxes attached to boneos, which can also serve as physical joints then, but with that also someone needs to integrate it.
I usually don't integrate such major features that change so much, because they usually generate a whole lot of new problems you have to solve in order to make them work with no bugs in game, which I don't have the time and the nerves for. I mean ragdolls and physics are well known to be one of the biggest sources for glitches in all kinds of games.