Comment by newdee
You’re not helping people by neglecting to point out errant use of messaging platforms. It harms productivity and is something that a manager should be treating. You don’t need to be “hard” about it, but not guiding people is arguably more harmful than maybe a couple of hurt feelings. Make things better.
On the efforts to guide people, I added small things like this to the rules of engagement. But there's just so many more things to frame in the context of team management that this becomes just a foot note.
What really harms productivity is lack of leadership, vision and organization. I try to avoid micromanaging this sort of thing.