I can see how one may have gotten this impression, but really your just looking at Kodi having a few different views of the same thing to cater to different use cases. The add-on section in settings allows for access that can be locked out for something like a kids profile as well as still having access if you don’t choose to maintain an add-ons category on your main menu. You can launch add-ons from the view in the settings, your just have to do it from the information screen which is also the default click action. The add-ons accessed through the other views are basically the same but they have a default click action normally of open instead. You can access the settings in any view by using the context menu or information buttons on your remote.
The view that your showing above with Estuary is actually called ‘widgets’ and they are something that can be added and modified in the OSMC skin. There is a how-to that covers tweaking this stuff that can be found here…