I don't actually use Obsidian's syncing feature or web publishing.

I use Obsidian to write and manage large collections of linked notes, like a personal Wiki; only I don't need to host a wiki somewhere, and the files are just plain text files. It's become one of my killer apps, one where I manage all of my background notes for the projects I work on. It suits the way I think, and I find it more useful and more friendly than other apps of its type.