Continued on my previous post, without further complicating, I think that the solution can be even simpler for development. While at the same time users who want something closer to private messaging can be satisfied.
Suggestion:
Option to group all private discussions under the Private Discussions tab.
https://i.imgur.com/RHdWOVw.png
It can be the same as All Discussions, but instead of showing all discussions from all tags, it will show only private discussions from all tags.
I would be more than happy to pay someone to "prioritize" work on this solution. Hope you will accept this and someone will get back to me 🙂