Earlier quoted context omitted.
We tried. Oh we tried. But the mobile apps being not native made the mobile usage drop like a rock compared to Slack, leading to the fact that it was harder to reach people than via the old Slack. When I saw that Rocket.Chat also used non-native clients leading to similar complaints, we just dropped the whole project and moved back to Slack.
That's a blessing in disguise, can avoid taking work with you everywhere you go.
I have a work phone that I take with me when I am on-call or on a customer site. Slack (or whatever we decide to use) absolutely has to work here.