What Slack's New WYSIYWG Editor Really Means: Slack unveiled a new WYSIWYG editor after using Markdown for years. You might wonder what this has to do with CMS, but this article from Vice sums it up in the headline:
[...] we're in a world where Markdown doesn't look mainstream, despite the fact it's in so many contexts that it’s already everywhere. Good luck selling that to the boss, though.
The article mentions Microsoft Teams, which supports Markdown but combines it with rich text (when you're done with a Markdown sequence, the editor makes it appear like rich text).
As a CMS integrator, we tried to get customers to accept Markdown early on, but WYSIWYG won out. Fair or not, Markdown suggests open-source, and people spending six figures on a CMS don't want that association.