System level preference for voice chat
Gamers who do not use voice chat, for reasons of impairment or otherwise, are routinely excluded from online gaming, kicked out by other players.
Text to speech and speech to text are not always an answer, even with the best technology there will be players who are simply not willing to communicate with others, through preference or due to a condition. It is unfair for these people to be kicked out of games, and unfair for players who want to use communication to be forced to play with gamers who do not communicate.
Being able to show other players what your communication preferences are would help. Setting a flag at system level for not wishing to take part in communication would mean that information could then read by developers for use in matchmaking, and communicated in-game through icons on player lists.