Semantically meaningful list headers and aria labels

I want to briefly play devil's advocate about semantically meaningful list
headings, because when we present the note, we need to assume people will
question our commentary.

Reading through the extensive commentary around the creation of the ARIA
digital policy module, I see that one of the most frequently pushed
requests is "why do you want a specific name for your industry for
something which already exists in the specification?"

So, what can be enabled by having a semantically meaningful list header,
that could not equally well be enabled by using aria-label (for offscreen
labels) or aria-labeledby (for visible labels)? These are the roles which
exist to provide the general-purpose ability to put a heading on any
element.

Deborah