How come AI's lost VOX?

[magic mountain]

Forget limits or whatever, just make VOX a module the crew has to install and can remove at any time. Somehow make it require another human somehow, no shell or cyborg shenanigans. Good AIs will get it, bad AIs won't, terrible AIs will get warned and then banned from AI, same as anything else.

Considering the failure of pretty much everything anyone ever made that required at least two people to cooperate for ten seconds I think this would be plenty.