been going around the block with note taking, onenote, evernote, apple notes, obsidian.
i realized that we should be using plain-text and avoid any such external systems if we want to remain free from lock-in.
there are only two forms that is guaranteed to last; plain text (.txt) or basic html (.html). yes, not markdown.
i really don't like markdown. just do plain-text, or choose html for a document format (if you must have markup)-- no conversion necessary.
that doesn't mean i don't think you should use markdown; rather, it can be an intermediate format. once you're done writing it, save the resulting output and archive /that/. you have no guarantees markdown will output as you expect in 10-20 years from now.
if you can edit the note with any editor you want and copy it anywhere, then that is freedom.