Correct. Posting in the discovery composer I have built is entirely context dependent. Why restrict it like this? Because the use case I’ve built it for ties categories to physical locations, giving them a somewhat different character to normal categories in a normal non-location-specific forum. If you’re specifically tying content to a location, you don’t really want your users to be so easily able to post new content in different locations. Someone can only be in one place at once.
*edit. If you’d like to discuss this further, let’s do so in the custom layouts plugin topic. It’s a little off topic here.