We've been using Mattermost for so long I don't know what happened to Slack but the fact that they can't keep their customers is not really an issue as long as

We've been using Mattermost for so long I don't know what happened to Slack but the fact that they can't keep their customers is not really an issue as long as we have similar software available for a more just cost or self-hostable. This type of app isn't supposed to hold data. At least in my opinion, Slack is more for instant messaging and e-mail for tracing.