It’s like having drinks at a bar solo, talking to people next to you (a bit more reserved, avoiding specific topics) vs. having drinks with a close friend. I don’t mind if someone listens to my private conversations with my friend, but the direct audience is different.
I was thinking that the OP for this comment thread was claiming that there are situations where public comments/knowledge sharing isn't needed for teams, which makes no sense to me.
For example: While working with text written by non-native speaker, had to explain often to some members of the team t hat the text was just awful and needed a complete rewrite. But I didn't want to type this in public so that the "culprit" wouldn't feel like I was out to get him or something.
At least in my culture, it is extremely rude to berate people in public, so I extended this to also considering rude to "blame" people in public when explaining why work is late.
Closed channels for teams are good but not everything is a democracy. I let my team make decisions but I can veto any of them, if needed.
If forcing all communication to be done in public makes the goal harder to achieve, then ffs do something else. Don't just force people to be inefficient because of some dogma.
The goal is not "make all communication public". The goal is to get the job done.
Just adding that "get the job done" shouldn't be confused with personal productivity. Many younger/inexperienced devs that are highly motivated go through a phase (some get stuck here) that optimizes their personal productivity above the team's productivity. You end up with pockets of people that share knowledge (or hoard knowledge) with others left behind. You also end up with different subsets of people making different decisions, younger devs clinging to each other for feedback/guidance (yikes), and way more thrash that needed.