Seems like general voice chat tendencies across different gaming platforms/games lean towards friends/party only chat because no one wants to listen to some random player's music blaring over mic, trolls, kids yelling/screaming (either in the background or the player behind the character, because some parents...), edgy hardcore elitists who've been just dying for an opportunity to throw their snark over voice instead of just chat, etc.

Seeing as we already have Skype/Discord/TS3/whatever for said friend-only chat, I doubt you'd see much usage of in-game voice on average. Instead you'd probably see an increase in usage of the phrase "Get on voice" and/or the addition of (|Please use voice chat.|) and (|I'm sorry, I can only type.|) to the auto-translate feature. ;p