Yes you can turn Medium comments into articles — they’re articles in the first place
I’ve always thought that the commenting system on Medium is broken — broken in the sense that it treats comments as articles. On the Stories overview (for us that writes here) there are no way to separate comments and articles. This has annoyed me a lot.
In your case, my annoyance may be exactly what you’re asking for.
If you hover over the “Go full screen” button in the comment box, a popup appears that says “Every response is its own story. Expand to the full-screen editor at any time.”
When you go full-screen you also get the formatting elements. Pictures, headlines, etc. So your comment *is* an article with its own URL; by using the formatting elements it’ll also look as one.
Hopefully this made sense to you (as you probably see, I did the things I wrote about here and turned a comment into a formatted article).