Proximity Voice in Games

Alright, you remember the thing in Halo 3 when you could hear your enemies talking if you got close to them?
Why can’t that be a thing for any game in general?
I’m not talking about only hearing enemies, I mean have it for your teammates too. The way it is now, you have to learn the “call outs” for the maps just to let someone know where the bad guys are.
How about just standing next to a teammate and saying “Hey we got two guys up ahead” or such and such.

Why doesn’t this exist in many games?

Because the mechanic is easily bypassed by using xbox party?

Okay so then the next thing I was going to say was like…
That thing in Halo 3 where you have to push on the d-pad just to talk to the team… Have that let you talk to the whole team and have non-dpad talk be proxmity.

It makes me question why the heck did you have to push on the d-pad just to talk?

And the point I’m trying to make is that it would be better if you were not in a party. Becuase right now, if you’re not, it’s the same freaking thing, everyone hears you. And no one freaking has to hear you. The only time I hear people talk is if they’re complaining about getting killed or something. You’re team can’t hear you if you’re in a party anyway.

And didn’t MW2 do that? They didn’t allow you to be in a party chat?

C’mon, has no one thought of this?