Not just Obsidian. I use the same directory of MD files for Obsidian, Zettlr and Typora. I've even configured the first 2 to auto-name new notes using the same custom date/time-based pattern. You can then use Jekyll (the GitHub pages engine) to publish/update specifically tagged/located notes to your blog or use PanDoc to convert them into an ePub for reading on a handheld device. Needless to say you can also use whatever a tool or programming language to do batch operations on the texts.

And by the way the Obsidian has just released an [optional to use] mobile app which makes keeping notes in it even more useful.

Whether you are a nerd or not, looking for the optimal self hosted note taking system is a super nerdy behavior. Just sayin'.

I've seen many people doing this even being far IT, science, collectibles or anything else nerdy. They mostly go Evernote though - because it is the most well-known. One day you just get overwhelmed with everything and start feeling like you absolutely have to organize all that chaos. Good note-takng suiting your needs can also feel helpful if you have even mild OCD or ADHD.

Everyone has mental structures for knowledge, this is just an extension. And I don’t want to think about sorts of questions like “who owns Notion today?”