This feature is still under review. The feature team is digging into the details but have not made a decision yet.
You can just expose SharePoint columns but you'd need to either make channels into libraries to support different column layouts or allow per-folder columns in SharePoint since that's what the file storage back-end really is.
The feature team has reviewed this item and decided to decline it at this time.
So by declining this you're basically saying an acceptable solution is to delete the Team/Channel because that's the only way to get rid of this Teams development artifact right now.
Since the web version of the text editor is built into SharePoint already, you might as well bring it to Teams.