I have the same problem. I don't understand your answer. Do I have to install some special custom theme for this to work? I am trying it with basic Vanilla theme and even when I have created specific passage key and associated it with category, even logged out users can see posts from this category.
No special theme is needed. Pages from your website are stored in the pages folder in your theme as you create them in the CMS section of October backend. (See: https://octobercms.com/docs/cms/pages )
The example I posted previously was the content of my page file for my "News" page. This file contains all the settings for that page and the components they contain. If you use this as a template for setting up your page then it should work as it does for me.