I feel like I came across that as I was weighing the various options for us to try haha. Zulip is the kind of thing I'd love to give a shot, but I have to take into account people who won't be tech savvy enough to use something like that. Therein lies Slack's value to us.

At the end of the day, Slack is really useful, but I just don't see its use getting expanded much. At least for us. There's lots of stuff that just shouldn't get communicated across there. Coordination across the sides of the business that don't use Slack wasn't an issue in the first place, it was never really even considered afaik.