@manton I think HTML and markdown have a complex relationship.
If I dial back to the HTML I wrote in 1996, it was very much a data output format. Eventually adding some cascading style sheets so that you could control some basic rendering of that data format.
But as the technology expanded, HTML and CSS have essentially become rendering and display formats. We deprecated H tags and P tags for DIV and SPAN tags. That's kind of when Markdown down came into existence. To render structured text without CSS concerns.
So I think the underlying question with a blog is really a decision about what you are trying to produce. Are you trying to produce a structured data file with some styling? Or are you trying to produce a digitally rendered interface?
In the case of a blog post, I can see both outputs as equally valid depending on context. So I can see value in both. This may be a case for author's intent. If an author doesn't intend for a markdown post, then maybe it can't be output that way?