I guess the question Rabid has (and to an extent, so do I) is how do you begin enforcing something out of your jurisdiction and is not able to be really looked into? Like, we know right now that certain people are using it, sure, and we can enforce that, but in less obvious situations you can really only suspect people.
I wasn't afraid to take action if I felt the case of suspicion was strong enough after numerous instances when I was in the admin/headstaff chair at TnB but I do think this is an important question to ask in regards to looking into how we tackle metagaming overall.
To be honest, if it were enforced, it would:
1. Discourage people from doing it, and increase the chances that some of them actually stop
2. Make it so that they have to be more subtle about it. Seeing two cops suddenly make a ladder without anything spoken ICly would mean they get reported.
3. Get rid of people who can't adapt and cease metagaming. Not a big fan of that, I understand some have their fun differently than others but if it has to come to this...
4. Remove the popular opinion that you have to be in VC. The main issue for me isn't that they do it, it's that they complain when people play differently. If the rules stated that you cannot be in VC, it would stop them from recruiting others into that line of thought, new players would just look at the rules and go: "No, I don't want to be in VC, too risky".
A large group of people freely voice chatting is destructive. A small group of people VCing and trying to be really discreet about it is drastically less destructive.