To be honest if you really REQUIRE voice comms for any EX content in this game, you're probably a little bad. They can help, but...other than a static, most people aren't interested in jumping into voice with a bunch of people who they don't know and have no synergy with. Most of the time people who make those groups are people who no longer have friends or were removed from even elitist places for having a big mouth, and small skills.
On the flipside? You can't be angry at people who honestly do want to farm and don't want to deal with new people. That's fine, IMO.