This game doesn't need any voice interaction, not even Twintania. An emote ( with text of what is coming and sound to alert) coordinates a whole group perfectly.
Some may prefer a mic to type. Lazyness , bad habit from OTHER mmos maybe (where maybe voice coordination was needed). The word "most" you used is surely not true. Not here at least.
The game also makes impossible a voice chit chat using functions like DF, so most are just silent. "Hi" "Goodbye, was fun". That's it.