David from the future: David's Daily Marginalia (also called David's Daily Journal) is now defunct. See the 20/ New Directions newsletter for more information.
Daily Marginalia has become the most freeing experience. A public/private place to post. Public because anyone can see it, but private because very few people come looking for it.
Plus, it's mine and no one else's.
I've been taught for a while never to rely only on social media as your single platform. At any moment, Facebook, Twitter, Instagram, or any of the others may change the way they operate, the terms and conditions, or (very doubtful) go out of business. And then all you work is lost.
Also, having it on a platform that isn't open and requires an account to access can separate you from potential readers/customers.
But this little place of mine has none of that and is 100% mine. Even if Ghost (the company that ~~runs~~ used to run my blogging software) goes out of business, they are open source, so I can run it on my own. Or I can export to another platform. All in all, I have that freedom.
So, while Daily Marginalia isn't for everyone, I think for a few, it's a good curiousity. But even if no one visited, I think I'd continue doing it for myself.