That’s the point. Assume you have 20 frames and they are all named (Rectangle) it would not be possible to select the right one. So renaming everything would be helpful, but also time consuming.
What is the purpose of creating frames and giving them no fill or stroke? Well, I didn’t say, that I would give them later such attributes or maybe put a picture in them, but I do not want to be limited with the standard-formatting (e.g. a light grey for everything).
In my opinion it should work as in InDesign:
1. Normal or layout mode: You see invisibles (white space characters), guides, bounding boxes of every frames
2. Preview Mode: You see your final result that would be printed, without invisibles, guides and bounding boxes
As mac_heibu described, this is what we learned 10 or 15 years from other layout programs.
Allthough it is good, not to clone everything from other programs, this is something that I expect as InDesign-Trainer with experience of 20 years how visibilty of elements should work in Publisher too. It seems no good habit to me, to identify something in the layers panel or rename 20 frames to identify later one ;-).
In the end, people would not move from InDesign to Publisher or even start with Publisher as their first app, if there is a another new cool feature, but think of usability and handling. Just my 2 cent, but displaying frame edges, colorizing guides, moving guides to a layer and distinguish between horizontal or vertical guides, magnetical columns guides, these are things that are pretty done in InDesign and hopefully come to Publisher as well.