The linked issue is probably useful if someone using Emacs/Org exports Org to Markdown format, and then uploads to a Github issue as that feature proposes. But then I fail to see the advantage of that flow vs just committing the Markdown file to any online git repo and letting Netlify etc. take care of publishing the blog.

Because.. uploading a Markdown file to a Github issue is one thing, but then what about refactoring, occasional post edits, etc.? Probably keep on overwriting the same Github issue with updated Markdown files?

You don't have to reply to these questions here.. just some thought if you do invest time in implementing this feature request.