I’d say in my experience it’s generally been true.  

Maybe this will make my opinion clearer.  Story systems have rules around pushing the story, which is their intent.  When you aren’t pushing the story they often fall back to just let it happen and move on.

Where I struggle with in running them and have struggled with in playing them is what is the cut off between a story moment and a non-story moment.   It’s that moment where I find they flounder because it’s not always so obvious.