The underlying purpose of org-mode is to manage this issue (the text part). It doesn't solve it, instead it is a tool for managing the steadily increasing archive organizational complexity within an ever evolving timeline. You reconfigure your archive's implicit schema well now you're in a world of heavy editing. That's life. If you don't have a solid backup strategy, you are going to lose stuff. That's also life. Big binary blobs are a different, equally important problem.

Sure, keep your archive text in markdown (which one? a dumb person asks). But I'd recommend managing it with org-mode, it doesn't really care what format your text is in.

(Yeah I saw the footnote mentioning org-mode but that reads to me that org-mode's reference there is entirely about the markup flavor.)