I noticed that the voices seem to have a cardioid or similar projection pattern for their voice, so that they are more clear and audible when facing towards the listener?
This would have a pretty nebulous but dramatic impact on how people interact in the game, and probably result in a lot of people having troubles hearing people in unexpected contexts. It's subtle and technical, so most people will not realize what the issue is.
For example if you are a group of people and running together somewhere, the person in the lead might be talking, joking, narrating something or whatever, but if their voice is just getting lost in the void in front of everyone and nobody behind can hear, this can be an issue.
People have been used to omnidirectional voice audio sources for years, and changing this would pretty widely impact people.
You can get somewhat used to it, but there's going to be a lot of cases where someone just wasn't as loud or clear as they should have been because they turned away, and it'll lead to volume confusion.
If anything i think it's sensible to have this only enabled when earmuffs are on; or perhaps something the world can override. It should probably be off by default.