I've spent quite a while working in spaces where the space is devoted to a team. If people are having quiet, focused discussions about what we're all focused on, I rarely find that distracting. The thing that drives me bonkers is when people are having loud, emotional, or off-topic conversations. Then part of my brain wanders off to process it and the rest is compelled to follow.
I also think Slack is rarely a good solution to trying to avoid interruption. If I turn it off for a few hours of coding, I'm far too late to participate. And if I leave it on, there are distractions right there on my screen. There's no way to overhear the useful bits and let the rest go; it requires full visual attention to process. The workplaces where I've felt least effective are the ones with big IM cultures.
While I'm not good at tuning out any kind of noise, I'd say I'm pretty much the opposite, in that an argument about football or (building) architecture is easier to work through than a "team" conversation that I'm reasonably sure isn't pertinent but contains enough relevant keywords to keep pinging me for attention. My point is that distraction is such a personal thing that the only way to mitigate it is to give individuals a fair bit of control over their environments.
Yes, IM can be a horrible distraction too. If you've got a question that needs some thought from everyone -- as opposed to chatter or ephemeral questions -- then truly asynchronous communication (yes, e-mail...) is probably a better bet.
Often I see "team" mean to use something much hazier, like "group of people with same skills" (e.g., design team) or "group of people in the same office". But I mean it more like "basketball team" or "soccer team".
In that environment, there is no team conversation that isn't pertinent, because we're all working to the same goal, and we're all jointly responsible for the same outcome.
That isn't to say that team members shouldn't work to be respectful. E.g., a team conversation over by the whiteboard is easier to let pass by than one where people are standing right behind me. But if we're on the same team, their problems are (eventually) my problems. I'd rather know sooner than later.
I think this trivializes OP's point a bit. It's definitely a lot more than 'off chance', and make people better collaborators is far from easy. Not saying that you're wrong, but whatever 'building Apple-like pods' is, doesn't sound like this is an option available to many (especially small) offices.
If you want a flexible collaborative environment without it's horrible effects on productivity, you could build Apple like pods surrounding an open area. Those who want to work in open areas would work in the middle. Those who need privacy to concentrate can still leave their sliders open during times they are open to collaborate.