It probably varies by job and by person. I find it helpful to talk with my coworkers, but a distraction to overhear them.
A lot of people (thought granted not everybody) find that after spending some time in a collaborative environment the background conversations move from being a distraction to an undercurrent of information. It becomes possible to tune it out but still hear keywords that might be relevant and allow for better teamwork.
A mailing list, irc channel, xmpp muc etc. allows me to collaborate on my terms. I can rethink and edit my response, and if I'm in the middle of something I can read it later and respond then. Conversations typically don't work like that.
That's true but your way has high latency. Conversations happen much faster.