My perspective is every form of communication bears certain unspoken rules / implications.
* Email - This is a serious thought out discussion
* Slack / Similar in a shared channel - This is office-formal, you should be professional but can joke around. Similar to how you would talk to an equal or your manager in person
* Slack / similar in DM - This is a rapid "Quick question" forum where you just need some links or quick thoughts. Nothing here is very serious
* Phone call - This is informal, rapid discussion for time sensitive issues. I'm calling you so that I don't have to page you.
My perspective is every form of communication bears certain unspoken rules / implications.
* Email - This is a serious thought out discussion
* Slack / Similar in a shared channel - This is office-formal, you should be professional but can joke around. Similar to how you would talk to an equal or your manager in person
* Slack / similar in DM - This is a rapid "Quick question" forum where you just need some links or quick thoughts. Nothing here is very serious
* Phone call - This is informal, rapid discussion for time sensitive issues. I'm calling you so that I don't have to page you.