Slack has raised our charges by $195k per year

Slack has been a down hill project for the past 5 years and has become incredibly bad.

Unfortunately,this should be the sentiment with all SaaS projects.

When a platform, like in this case, is inherent to the value proposition and can not easily be exchanged (building programs around it), one should consider self hosting.

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.

This is licensing problem, not hosting problem. VMware and Oracle didn't got it reputation out of thin air.

If you’re going to spend the effort to rewrite your chat conversations back into email, you might as well throw those summaries into a wiki or other documentation system..

You are right, but when self hosting you do have a bit more leverage - such as not being rug-pulled by the SaaS provider before having gone through arbitration.

Organizations need to realize that being right does not matter if you are dead.