For some history and background, see a prior attempt to do release notes in D12163.
We got pretty far, but some process concerns derailed it. I think we could probably get it done if we adjust our process or the scripts used to facilitate it accordingly. I noticed recently that GNOME apps released for 3.32 now have release notes in AppStream. It looks really good in Discover:
They even list the contributors who implemented each new feature or bugfix, which is really nice!