First, yes I know that if you double-click the size handle the text frame automatically resizes to fit the text.
Also, if I want to have a text that is not restricted to any text frame I could just use artistic text.
But there are still problems without a dynamic size option just like the one in InDesign.
Most obviously it's just more convenient to tell the text frame to dynamically resize to it's content than double clicking the size handle every single time.
When I want to give the text a colored background of course, I want to have a margin between the text and the background. You can only have this margin with a text frame and not with an artistic text.
An artistic text automatically sets its with AND the height. You can't tell it to only set the widht OR the height.
You can't just click the size handle to resize the text when the content of the text frame is not text you manually enterd but a field (Text->Insert->Fields or View->Studio->Fields). The lenght of that text can change, so setting the text frame to a fixed size, manually or atomaticcaly, isn't a good idea.
Here's a use-case why we need a better solution.
I was using named sections in my document and I wanted to show the name of the section in the top left corner of the pages. So I made a master page and there I put a text frame and inserted the section name as a field. Of course, on the master page I only see the placeholder "<sectionname>" and when I double-click the size handle, Publisher will set the size of the text frame to the size of the placeholder, which doesn't make any sense. When I look at that text frame on the actual pages the size is always the size of the placeholder, no matter if the actual section name is longer or shorter.
I wanted it to have a colored background to be more visible. That's why I couldn't just use an artistic text. I could still set a colored background there but I can't set a margin between the text and the border of the colored background. That way the text looks like its squished into that colored rectangle.
So how to make it better? Basically just like InDesign (or even better).
You can tell the text frame to have a dynamic size which depends on its content.
You can choose between no dynamic size (default), only height, only width, height and width, height and width (keeping the aspect ration).
You can choose if when resizing the left/top, center, or right/bottom will have a fixed position.
You can set a minimum height/widht. Perhaps a maximum height/width also would be a good idea.
You can choose to have no line-breaks at all.