I posted a feature request as an answer to this question.
https://community.tribe.so/question/5b88379890ecbe6751123d8b

Here is the answer URL, which doesn't work now and I am unable to find my answer as well.
https://community.tribe.so/question/5b88379890ecbe6751123d8b#answer-5de75c126b71a81f89069902

Screenshot of the answer which I posted and can still be seen from my profile, but not available on the question thread?
https://share.getcloudapp.com/7KuyJwLo

I am just curious to know if this has been removed or is it a bug? 

There should be something like private topics or to limit any topic from public posting.

Here is a good example, on your forum, someone posted a question in the "Release Note" topic. That should be only tagged/posted by community/group Admin/Moderators.
 

https://community.tribe.so/question/5dd84d28df4e416ca3228abe