Currently I am using a set of markdown editors: Ulysses[^1], Typora, iA Writer and a few others. That makes me interface agnostic. The most important thing is the content, the (markdown)text I am producing. I can't say that about text in org-mode. It's tied to Emacs.
(Edit:)
In Ulysses I started using an annotation system myself, that's why this project here caught my attention. I am experimenting with brackets, double brackets, colons, double colons. Still in the process of experimenting.
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[^0]: was using org-mode to write documentation, journal entries, and as a task management system
[^1]: Ulysses is way more than an editor. It is like Evernote with markdown targeting authors. It‘s my ‚Zettelkasten‘