It's one more information stream I have to monitor, by manually going and checking it. Even if work used Slack - we don't - I'd still have to manually navigate among teams to cycle through all my incoming communications. And bringing additional colleagues into the conversation on a purpose-specific, temporary basis is much higher friction than it is with email. Instead of just CCing them on an email, I have to get them invited to that company's Slack, and they have to go through the hassle of setting up an account. And then, since they didn't install the app, I still have to manually prompt them to sign in whenever I see that they aren't remembering to include that Slack in their manual rounds. Which they aren't, because Slack Connect is oftentimes their first experience with having to do manual rounds to purpose-specific locations in order to communicate with people like that.

I've never really got their "move out of siloed email communication" sales pitch. It's like, out of the silo and into a different silo that's deeper and also on fire.