Sorry, I thought you were asking how to get it to work… Yes, the Carbon feature should be hidden when the framework is set to Cocoa, so perhaps submit a feedback for it…
If it is only used in Carbon and other Carbon features have been moved to the advanced Inspector panel, then I don’t see it being an issue (I am going to assume that Carbon support will be dropped sooner or later)
While we are at it, isn’t it a good idea to place Control Location/Size and Lock in another advanced pane ?
I set them once, and usually never change these properties.
It can be done (split displayed properties into advanced panes) taking into account the number of times (often, rarely) the set of properties are used
A maximum number of icons (in one line) have to be set too (two lines ?) because it will be counter time saving to search where is my Advanced icon ?.